NREL is a national laboratory of the U.S. Department of Energy, Office of Energy 

Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

Contract No. DE-AC36-08GO28308

Solar Ready: An Overview of 

Implementation Practices

Andrea Watson, Linda Giudice, Lars Lisell, 

Liz Doris, and Sarah Busche

Technical Report

NREL/TP-7A40-51296

January 2012
NREL is a national laboratory of the U.S. Department of Energy, Office of Energy 

Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

National Renewable Energy Laboratory

1617 Cole Boulevard

Golden, Colorado 80401

303-275-3000 • www.nrel.gov

Contract No. DE-AC36-08GO28308

Solar Ready: An Overview of 

Implementation Practices

Andrea Watson, Linda Giudice, Lars Lisell, 

Liz Doris, and Sarah Busche

Prepared under Task No. SM10.17X6

Technical Report

NREL/TP-7A40-51296

January 2012
NOTICE

This report was prepared as an account of work sponsored by an agency of the United States government. 

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Sponsor

This report was made possible through funding from the U.S. Department of Energy (DOE) 

Solar America Communities program. To learn more, please visit 

www.solaramericacommunities.energy.gov.

Acknowledgements

Thanks to Keyes and Fox, LLP; Amanda Bybee, Namaste Solar; Chris Klinga, Lighthouse Solar; 

James Critchfield, EPA; Misty Conrad, Sarah Truitt, Jason Coughlin, Sheila Hayter, Jesse Dean, 

and Rachel Romero, NREL, for their contributions to this report.
iv

Table of Contents

Introduction ................................................................................................................................................. 1

Solar Ready and Costs............................................................................................................................... 3

Solar Ready Legislation and Policy .......................................................................................................... 8

Solar Ready Certification ......................................................................................................................... 15

Stakeholder Education and Communication Methods ......................................................................... 19

Conclusion................................................................................................................................................. 23

Appendix A – Trade Organization Resources........................................................................................ 24

Appendix B – Sample Solar Ready Legislation ..................................................................................... 26

Appendix C – Sample of Solar Ready Requirements or Practice by Jurisdiction ............................. 30
1

Introduction

According to the U.S. Census Bureau and U.S. Department of Housing and Urban 

Development’s January 19, 2011, report on new residential construction, 7.8 million new, 

privately-owned housing units were completed in 2010.

1

A solar ready building is engineered and designed for solar installation, even if the solar 

installation does not happen at the time of construction. The solar ready design features, if 

considered early in the design process, are typically low or no cost. Attention to building 

orientation, available roof space, roof type, and other features is key to designing solar ready 

buildings. The Solar Ready Buildings Planning Guide, published by the National Renewable 

Energy Laboratory (NREL) in 2009, details the technical processes for making buildings solar 

ready.

These homes, if not compatible with 

solar technology, represent a large barrier to widespread solar deployment. Once a structure is 

built, structural and solar access issues can prevent a solar project from being cost effective, and,

in some cases, can make it entirely infeasible. Currently, when developers and solar installers 

assess buildings as potential solar sites, they sometimes dismiss buildings that are incompatible 

with a solar installation. While solar could be pursued, the potential solar production is 

significantly reduced, making payback periods longer and financing less appealing. Homes and 

commercial buildings built “solar ready” offer a solution to overcoming this installation barrier 

to renewable energy.

2

Solar ready design is important if photovoltaic (PV) or solar hot water (SHW) technologies are 

to be installed on a building at any time during the building’s lifespan. Solar ready also allows 

owners to take advantage of a changing energy market. The economics for installing solar on a 

new building are not always compelling, but, in the future, that picture could change with rising

electricity prices and/or falling solar technology costs. In some locations, installing SHW is now 

cost effective for new construction projects. Building a home or commercial building that is not 

solar ready exposes owners to the risk of not being able to take full advantage of future economic 

scenarios for solar electricity and hot water. Instead, the building owners have no option but to 

continue to buy conventional power or pursue solar with a lower return on investment due to the 

structural or solar access barriers on their buildings. While installing solar at the time of 

construction is encouraged, when this option is cost prohibitive, solar ready could be a standard 

and common alternative.

In cases in which it is not cost effective or feasible to install a solar system at the time of 

construction, creating a solar ready structure improves the cost effectiveness of solar when 

pursued at a later date. This eliminates barriers to future solar applications and facilitates market 

growth.

It is important to recognize that solar ready itself does not reduce energy use or replace 

conventional energy with green energy. Solar ready does not contribute toward carbon emissions 

reduction until actual solar capacity is installed. Instead, solar ready has the potential to act as a 

 1 Economics and Statistics Administration. New Residential Construction Report. 

http://www.esa.doc.gov/sites/default/files/ei/documents/2011/January/new_residential_construction_december_201

0.pdf. Accessed April 2011. 2 L. Lisell, T. Tetreault, and A. Watson. The Solar Ready Buildings Planning Guide. NREL/TP-7A2-46078. Golden, 

CO: National Renewable Energy Laboratory, December 2009. Available online at 

http://www.nrel.gov/docs/fy10osti/46078.pdf.
2

catalyst for future installations and market expansion by reducing balance of system costs at the 

time of installation. In order to see this benefit, solar ready must become a widespread practice.

This report will explore three mechanisms for encouraging solar ready design and construction: 

solar ready legislation, certification programs for solar ready design and construction, and 

stakeholder education. These methods are not mutually exclusive, and all, if implemented well, 

could contribute to more solar ready construction.

Solar ready legislation is a way to mandate the uptake of solar ready practices. The Solar Ready 

Legislation and Policy section of this report describes the pros and cons of such an approach and 

discusses potential interactions with other policies. Appendix B includes sample solar ready 

legislation.

Certifying solar ready may occur through a solar ready certification program or through 

integrating solar ready into existing programs, such as the U.S. Department of Energy (DOE) 

and the U.S. Environmental Protection Agency (EPA) ENERGY STAR program3 or the U.S. 

Green Buildings Council (USGBC) Leadership in Energy and Environmental Design (LEED)4

Education of stakeholders can occur in conjunction with solar ready legislation or certification or 

as a standalone effort. Education of stakeholders will be an important step in widespread 

adoption of solar ready practices.

program. Certifying a building or home as solar ready can work toward the long-term goal of 

reducing costs and carbon emissions over time. Certification helps the building owner advertise 

solar ready status and signifies the potential of the structure to take advantage of solar 

technologies later in the building’s life. In addition, certification helps raise awareness among 

property owners who may otherwise not have considered solar at all. However, certifying solar 

ready offers a reward for a measure that does not save energy, produce clean energy, or reduce 

emissions.

This report is intended for local, state, and federal decision makers as an overview and 

discussion of tools and methods for promoting widespread solar ready building practices.

 3 ENERGY STAR. http://www.energystar.gov/. See “Certification”/“Designed for EnergyStar.” Accessed April 

2011.

4 LEED Homes Rating System. http://www.usgbc.org/DisplayPage.aspx?CategoryID=19. Accessed April 2011.
3

Solar Ready and Costs

When a building owner attempts to install solar on an existing building that is not solar ready, the 

owner may experience the following:

• Structural or solar access barriers that prevent installing solar due to insurmountable 

costs

• A less attractive financial picture due to reduced solar production

• An increase in cost to make the building compatible with solar.

All of these scenarios may slow or stop the rate of solar installations, and all can be avoided 

through solar ready building practices. This section explores the costs of solar ready, which can 

be used as background information for discussing the methodologies of promoting solar ready 

throughout this report.

Cost Prohibitive Scenario

In some cases, installing solar on a pre-existing building is cost prohibitive. Structural barriers or 

solar access issues can create a scenario where it is not feasible to install solar. Table 1 highlights 

these issues, as well as the cost scenarios that could make a project infeasible, the potential fix 

with solar ready design, and additional comments. 

Table 1. Cost Prohibitive Scenario

Structural or Solar 

Access Issue Potential Cost Solar Ready Fix Comments

Roofs unable to 

accept added load of 

PV or SHW system, 

especially if ballast 

system is only option

A cost-intensive roof 

reinforcement may be the 

only option, making a 

solar project cost 

prohibitive.

Design roofs for anticipated 

loads associated with a 

future solar installation

during the initial building 

construction.

This varies by location and may be 

more common where roofs are not 

designed for snow loads or where 

wind loading is especially high.

Significant* number of 

roof obstructions

Roof obstructions may be 

numerous enough that 

the added cost of building 

around them or moving 

them, along with the loss 

of solar production,

makes the project 

infeasible.

Group roof equipment on 

the north side of the roof or 

locate vents and other 

equipment to utilize nonrooftop space.

This will more likely make a project 

infeasible in the commercial sector.

A third-party financier—crucial to 

making many commercial solar 

projects move forward—may 

dismiss projects lacking sufficient 

continuous roof space.

Significant* shading Many things, including 

architectural features, 

other buildings, and 

vegetation, can cause 

significant shading. When 

the shading is very 

extensive and 

unavoidable, the 

economic case for solar 

is difficult to justify.

During the design phase, 

ensure that architectural 

features and the building’s 

position on the site 

minimize shading. Consider 

landscape architecture that

does not shade the roof in 

the future.

Shading may be more common in 

highly vegetated areas or places 

with high-density buildings, such 

as large cities. The effect of 

shading on PV power production is 

greater than that to SHW thermal 

production.

* The actual value of “significant” will vary by region, sector, or technology.
4 

An entity that could take advantage of a production-based local incentive would be more affected 

by production losses than one that could take advantage of an installed capacity-based incentive, 

although some installed capacity-based incentives do consider potential production. 

Reduced Production Scenario

In many cases, a building with structural or solar access barriers to solar can still be compatible 

with solar. However, the structural or solar access issues can increase up-front system costs or 

reduce system output. Structural issues such as roof load limitations require the need for 

structural reinforcement, in turn increasing up-front costs and total system size. Daily or semiannual shading and roof obstructions that either shade or reduce the available roof space for solar 

can reduce the output of a solar system. Likewise, a non-ideal building orientation reduces 

system output. The example below highlights the difference in production when roof orientation 

is less than ideal. 

Example: Effect of Orientation on PV 

A 10-kilowatt (kW) PV array in Golden, Colorado, facing south and tilted 25° can be 

expected to produce 14,304 kW hours (AC) per year with an annual energy value of 

$1,201.00. (The state average electricity price is 8.4¢ per kW hour.) The same system facing 

east will produce 11,997 kW hours (AC) per year with an annual energy value of $1007.75. 

A west-facing system will produce 10,999 kW hours (AC) per year with an annual energy 

value of $923.92. This represents a 16% to 23% reduction in PV production and cost savings 

when oriented 90° away from south. Table 2 presents a simplified financial analysis of this 

example. 

Table 2: Effect of Orientation on Finances for a 10-kW PV Array in Colorado

Orientation Installed 

cost

Annual solar 

energy 

production 

value (8.4¢) 

Cost after utility 

rebate program of 

$2/watt (this rebate 

based on installed 

capacity, not 

production)

Approximate cost 

after incentive mix, 

about 45% of cost 

(e.g., income tax 

credit, accelerated

depreciation)

Simple 

payback 

period

South $60,000 $1,201.00 $40,000 $22,000 18.3 years

East $60,000 $1,007.75 $40,000 $22,000 21.8 years

West $60,000 $ 923.92 $40,000 $22,000 23.8 years

The example above illustrates that orienting a building to maximize solar production can shave 

years off the payback period for a solar installation. In the example, the utility rebate program is 

based on installed capacity, not system production. Some rebate programs degrade incentive 

levels for systems that are not optimally configured, but this degradation was not considered 

here. An incentive program based on production would further increase the simple payback 

periods for installations facing away from south. Similar calculations can be made to account for 

reduced array size due to roof obstacles or reduced production due to shading; however, these 

scenarios will vary greatly from site to site. 
5 

When confronted with a scenario in which expected solar production is reduced, some building 

owners may choose to pursue solar despite the less attractive economics, while others may 

choose not to proceed at all. Designing a solar ready building can prevent the production losses 

that negatively affect solar installation economics later in a building’s life. Solar ready buildings 

designed with continuous roof space uninterrupted by roof equipment, minimal roof shading 

throughout the year, and a roof oriented on an east-west horizontal axis can increase production 

and shorten simple payback periods. 

Incremental Cost of Solar Retrofit

There is always a cost associated with retrofitting a building to accommodate solar. With the 

proper solar ready preparations, these measures may cost less if done at the time of building 

construction. The examples below consider cost differences between preparing a building for 

solar during initial construction and after initial construction. Quantifying these incremental costs 

is difficult because of site variations. The scenarios below are examples of cost reduction 

scenarios, but these examples cannot be extended to every situation. 

Example: PV System

In this example, the costs are calculated for making a residential building solar ready for a 

10-kW PV system. For this example, there are three main measures associated with making 

the building solar ready that can increase the cost of construction. They include upsizing the 

electrical panel, installing conduit and wire from the roof to the electrical panel, and 

installing a combiner box on the roof in which to combine the wiring for the panels. The 

costs for these measures were estimated using the 2011 edition of RS Means Construction 

Databook. By these calculations, the building can be made PV ready for $1,729 at the time of 

construction. See Table 3 for the cost breakdown of the measures. 

If there were no solar ready preparations made at the time of construction, the same 

preparations would cost $4,373 at the time of solar installation. The measures would be more 

costly after construction for a number of reasons. Installing the measures during construction 

could be completed by a general contractor already on the site instead of requiring a team of 

solar contractors to travel to the site. This results in a 75% savings in the labor costs due to 

reduced travel time. In this example, vent relocation and inhibited roof exposure require the 

solar panels to be installed on multiple pitches. Both of these additions result in additional 

expenditures. The cost of the materials was assumed to be the same whether the work is done 

during or after construction. In this example, the measures completed during construction 

saved $2,644. 
6 

Table 3: Cost to Make a Building Solar Ready5

During Construction After Construction

Measures Equipment Labor Total Equipment Labor Total

Increase size of 

electrical panel $459 $480 $ 939 $459 $1,200 $1,659

Run conduit $374 $416 $ 790 $374 $1,040 $1,414

Relocate vents n/a n/a n/a - $ 300 $ 300

Install panels on 

multiple pitches n/a n/a n/a - $1,000 $1,000

Total $833 $896 $1,729 $833 $3,540 $4,373 

In this example, implementing the solar ready measures during building construction costs 

60% less than the measures would cost after construction. 

 

5 Waier, P.R., ed. Green Building Cost Data. RSMeans, 1st Annual Edition, Norwell, MA: RSMeans, 2010. 
7 

Example: Solar Hot Water System 

In this example, the costs are calculated for making a residential building solar ready for a 

three-panel, 96-ft2

, closed-loop solar thermal system. It is assumed that the system utilizes 

.75-inch tubing, and that the existing hot water system requires the addition of “stub-outs” in 

order to allow the SHW system to be incorporated without depressurizing the domestic hot 

water system. For this system, there are three main measures that will increase the cost of 

the building construction. They include installing copper pipes from the roof to the utility 

room, adding tee joints to the existing system where the SHW system can be plumbed in, 

and adding SHW mounting hardware on the roof of the building. By implementing these 

measures during construction, the building can be made SHW ready for $1,588. 

Table 4 shows the cost breakdown of the measures. If there were no solar ready preparations 

made at the time of construction, the same preparations would cost $4,645 as a retrofit. The 

measures would be more costly after construction for a number of reasons. Installing the 

measures during construction could be completed by a general contractor already on the site 

instead of requiring a team of solar contractors to travel to the site. In this example, the 

result is a 72% savings in the labor costs due to reduced travel time. In this scenario, there 

are vents that need to be relocated and roof exposure that cannot be optimized, resulting in 

panels that need to be installed on multiple pitches. Both of these additions require 

additional expenditure.6

Table 4: Cost to Make a Building SHW Ready

The cost of the materials was assumed to be the same whether the 

work is done during or after construction. In this example, the measures completed during 

construction saved $3,057. 

7

During Construction After Construction

Measures Equipment Labor Total Equipment Labor Total

Add mounting 

hardware SHW $8.00 $20.00 $28.00 $8.00 $50.00 $58.00 

Pipes to roof $407.00 $1,109.00 $1,516.00 $407.00 $2,773.00 $3,180.00

Stub-out pipes $2.00 $43.00 $45.00 $2.00 $ 106.00 $ 108.00

Relocate Vents n/a n/a n/a – $ 300.00 $ 300.00

Install panels on 

multiple pitches n/a n/a n/a – $1,000.00 $1,000.00

Total $417.00 $1,172.00 $1,589.00 $417.00 $4,229.00 $4,646.00

In this example, implementing the solar ready measures during building construction costs 66% 

less than the measures would cost after construction.

 

6 Waier, P.R., ed. Facilities Maintenance & Repair Cost Data. RSMeans, 18th Annual Edition, Norwell, MA: 

RSMeans, 2010. 7 Waier, P.R., ed. Green Building Cost Data. RSMeans, 1st Annual Edition, Norwell, MA: RSMeans, 2010. 
8

Solar Ready Legislation and Policy

This section discusses solar ready legislation or policy tools that may be useful in promoting 

solar ready. In preparing the sample legislation in Appendix B, NREL worked with Keyes and 

Fox, LLP, to evaluate a variety of different approaches that have been taken by states and 

municipalities in requiring new building construction to be solar ready. Keyes and Fox, LLP,

drafted the sample legislation in Appendix B to provide a starting point for jurisdictions 

interested in creating solar ready legislation.

There are a number of policies that could be considered when designing solar ready legislation 

and several that can act as standalone policies to promote solar ready. The following solar ready 

legislation discussion explains some of the choices reflected in the sample presented in Appendix 

B. This section also highlights some complementary policies and options that could strengthen 

the effectiveness of solar ready legislation.

Requiring solar ready construction through legislative or regulatory mechanisms has certain 

advantages, but may work best when combined with some of the other tools discussed below,

such as certification programs or education strategies. One of the biggest challenges of 

legislation is the ability to craft stringent rules requiring buildings to be solar ready while also 

allowing developers to achieve established requirements in a manner well suited to a particular 

building type and a developer’s design goals. Working in coordination with developers and 

builders helps make legislation more politically feasible. It is also important that legislation 

enables the use of the most cost- and resource-efficient technologies as they evolve. 

Currently, several jurisdictions have put in place some sort of policy that promotes solar ready 

construction (see Appendix C). However, there is currently little data on the effectiveness of 

these policies by metrics. More data, such as the number of new solar ready structures as a result 

of policy or the increase in the number of solar installations, needs to be collected on existing 

policies. Future policies should also plan for data collection and verification of policy 

effectiveness. 

Mandating Solar Ready Buildings or a Solar Ready Option

It is important to highlight the difference between solar ready legislation that mandates solar 

ready versus legislation that requires a solar ready option. A number of states have required that 

the option of solar readiness be expressly given to homebuyers at the time of construction. 8,9,10

 8 New Jersey AB 1558. 

Instead of imposing a requirement on new construction to be solar ready, this option focuses on 

educating the homeowner about solar technologies, providing them with the information to 

decide if the added cost of building solar ready is of value to them when they consider how 

future energy costs will impact their budget. Conversely, the sample legislation in Appendix B

has been drafted to require that new residential and commercial construction be solar ready. One 

of the limitations of the “option” approach is that relatively few homes and commercial buildings 

http://www.njleg.state.nj.us/2008/Bills/PL09/33_.PDF. Accessed April 2011. 9 General Assembly of the State of Colorado: Section 1, Article 35.7 of title 38, Colorado Revised Statutes. 

http://www.leg.state.co.us/clics/clics2009a/csl.nsf/fsbillcont3/56DAD78B9D26BD5187257539006E7FF9?open&fil

e=1149_enr.pdf. Accessed April 2011. 10 Online Code and Environment Advocacy Network (Ocean). http://bcap-ocean.org/state-country/colorado. 

Accessed April 2011.
9

are constructed with the ultimate buyer in mind. Unless the developer or builder will be the 

ultimate owner of a structure, choosing the solar ready option may not be appealing. 

Consideration of the variety of owners of a building over its usable lifetime increases the appeal 

of solar ready construction so that a long-term tenant or future owner could easily install solar.

Installing a solar system on a solar ready building can be more cost effective than installing solar 

on a building that is not designed to accommodate solar. Some features, such as orientation or 

shading, may not be reasonable to modify at a later date (see “Solar Ready and Costs” section). 

In addition, requiring a building to be constructed solar ready from the start may provide 

additional motivation for initial building owners to look more seriously at solar options in 

connection with the initial investment in constructing a residential or commercial building.

Along with mandating solar readiness for new construction, it may be effective to also require 

that future building owners be informed of options for having a solar system installed at the time 

a building is first constructed. Colorado and New Jersey have instituted requirements of this 

sort.

11,12 Software tools, such as In My Backyard,13 can provide information to an 

owner/developer on what a building’s exposed surface area could produce with a PV array 

installed. Likewise, the NREL SolOpt14

Solar Ready Sample Legislation

tool can be used to determine if solar hot water or PV 

makes more sense for a given amount of roof space on a particular building. Developers could be 

required to provide such information to educate buyers on the potential benefits of installing a 

solar system.

The sample legislation in Appendix B has been drafted such that state or local agencies have the 

opportunity to consider local conditions and policy appetite in promulgating detailed regulations

for solar ready building requirements. Although detailed requirements could simply be included 

in statutory language itself, there are a number of advantages to having the detailed 

 11 General Assembly of the State of Colorado: Section 1, Article 35.7 of title 38, Colorado Revised Statutes. 

www.leg.state.co.us/clics/clics2009a/csl.nsf/fsbillcont3/56DAD78B9D26BD5187257539006E7FF9?open&file=114

9_enr.pdf. Accessed April 2011. 12 New Jersey AB 1558. www.njleg.state.nj.us/2008/Bills/PL09/33_.PDF. Accessed April 2011. 13 NREL. In My Backyard. www.nrel.gov/eis/imby/. Accessed April 2011. 14 SolOpt Optimization Tool, available at the Solar America Communities website. 

http://solaramericacommunities.energy.gov/Publications.aspx. Accessed April 2011.

Colorado HB 1149

In Colorado, HB 1149 was enacted in May 2009, requiring builders of single-family homes 

to offer solar as a standard feature to all prospective homebuyers. Builders are required to 

give the buyer the option to either have a PV system or a SHW system installed on the new 

home, or to have all the necessary wiring and/or plumbing installed so that the homeowner

can easily add a solar system at a later date. The builder must also provide the buyer with a 

list, maintained by the Governor's Energy Office, of every solar installer in the area so the 

buyer can obtain expert help in determining if the home’s location is suitable for solar and 

what the estimated cost savings would be (General Assembly of the State of Colorado: 

Section 1, Article 35.7 of title 38, Colorado Revised Statutes).
10

specifications included in regulations. Principally, regulations are generally easier to update and 

modify over time. Given that technologies change, the ability to update technical requirements 

without action from the legislature is important to providing necessary flexibility. However, 

legislators can include more prescriptive language about technical requirements in the legislation 

if preferred. The technical requirements that NREL currently recommends have been provided in 

footnotes to the sample legislation for further guidance to implementing agencies.

If time and resources are not available at an implementing agency level, an effective solar ready 

statute can be drafted that avoids the need for further regulatory action by including specific 

requirements directly in a statute itself.

Commercial and Residential Considerations

The sample legislation in Appendix B applies to both commercial and residential construction.

Although many of the existing solar ready mandates adopted in the United States only apply to 

single-family residential buildings, there are similar cost challenges associated with modifying 

commercial construction that make extension of these mandates to such buildings a sensible 

approach. In particular, commercial buildings often have flat roofs that require ballast-mounted

systems. Commercial building roofs need to be designed to withstand the added weight of solar 

systems. The varied nature of commercial buildings requires more detailed regulations to be 

adopted to accommodate a range of building types. States may also want to consider whether 

multi-family residential and multi-unit commercial buildings warrant separate regulatory 

guidance.

Sample Legislation and Incentives

The sample legislation in Appendix B includes a provision to make it clear that compliance with 

solar ready mandates is not required for homes constructed prior to the statute to access any 

available incentives for solar installations. A new building that complies with the statute should 

also be able to access incentives under the theory that the costs of installation will be less.

Green Building Codes

Solar ready requirements can be a low-cost and effective addition to existing green building 

codes. Jurisdictions with green building codes using a points-based system may consider 

assigning points for aspects of solar ready construction, while providing additional points for 

homes that have actual solar systems installed. The text box highlights the residential rating 

system used in Pima County, Arizona. While this program is designed to promote solar ready

and ultimately increase the number of solar installations, preliminary data needs to be collected 

on whether this program is effective or if most developers choose not to comply.
11

Pima County Regional Residential Rating System – Tucson, Arizona15

The Pima County Regional Residential Rating System was developed to promote the 

construction of sustainable homes specifically designed for Pima County. Homes are rated 

and awarded points for environmentally responsible criteria including location, lot design, and 

development as well as resource and energy efficiency. Solar ready (SHW and PV stub-outs) 

qualifies for points within this system. There are four levels of certification available that 

range from Bronze (75–100 points) to Emerald (over 160 points). This voluntary, no-cost 

program is combined with the permit and inspection process. The procedure for obtaining the 

rating includes looking at site development and resource, energy, and water efficiency. Once 

one completes the procedure of complying with the requirements of the program, the building 

receives a certificate indicating the award level and becomes eligible to receive a building 

plaque to commemorate the achievement. For more information, see

www.pimaxpress.com/green.

Homeowners’ Associations

Jurisdictions may consider including language that addresses how solar ready requirements 

interact with limitations imposed by homeowners’ associations or common interest communities 

(CICs) rules. Although homeowners’ associations cannot trump requirements imposed by state 

law, homeowners’ associations that adopt rules directly or indirectly prohibiting the installation 

of solar equipment may undermine the intent of requirements that buildings be constructed solar 

ready. For example, states and localities include provisions that explicitly prohibit homeowners’

associations from implementing restrictions that prevent homeowners from installing solar 

energy equipment on their own property (e.g., Arizona16). In this case, jurisdictions may consider 

expressly preempting homeowners’ associations from prohibiting solar installations when 

enacting solar ready legislation. In Colorado, HB 08-1270 revised an existing law so that 

installation of renewable energy or energy efficiency equipment cannot be prohibited.17 The bill 

prevents CICs from making rules that would explicitly prevent the installation of such 

equipment; however, the bill allows reasonable restrictions based on aesthetic considerations, 

safety requirements, and—in the case of wind-electric generators—noise.18

 15 Pima County Regional Residential Rating System, Tucson, Ariz. http://www.pimaxpress.com/green. Accessed 

April 2011.

16 Database of State Incentives for Renewables & Efficiency (DSIRE). Arizona: Solar Rights 

http://dsireusa.org/incentives/incentive.cfm?Incentive_Code=AZ07R&re=1&ee=1. Accessed April 2011. 17 Colorado General Assembly. House Bill 08-120. 

www.leg.state.co.us/clics/clics2008a/csl.nsf/fsbillcont3/3F45E0C88F60DD39872573680059F7E2?open&file=1270

_enr.pdf. Accessed April 2011. 18 Colorado General Assembly. Digest of Bills. 

www.state.co.us/gov_dir/leg_dir/olls/digest2008a/PROPERTY.htm#08-1270. Accessed April 2011.
12

Historic Structures

The sample legislation in Appendix B only applies to new construction, so it is not likely to 

impact existing historic structures. However, new construction within a designated historic 

district may be under restrictions that inhibit the ability of a developer, or eventual owner, to 

install a solar system. As with homeowners’ associations, it may be wise to consider expressly 

preempting any such restrictions or to provide for an exemption for particular circumstances.

Solar Access Laws

Another potential companion provision may be the creation or enhancement of solar access 

rights. There is an exception from compliance in the sample in Appendix B for buildings that do 

not have sufficient solar resources to warrant the addition of solar readiness at the time of 

construction; however, this exception does not protect a building that may have sufficient solar 

resources at the time of construction from future obstructions that may diminish access to solar

resources. To ensure that initial investment in solar ready construction maintains its value over 

time, it may be worth considering companion provisions to enact solar access protections.

Nearly 80% of the states and a number of localities have implemented some type of a solar 

access law. As these policies are designed to meet the unique needs of the constituents, they vary 

greatly. For example, some of these policies allow parties to voluntarily enter into an agreement 

to protect the solar easement rights of either or both parties (e.g., Georgia19). Other policies 

require that solar access is not impeded (e.g., the City of Sebastopol, California20

Like many solar ready policies, data is needed on the effectiveness of these laws to protect solar 

access and encourage solar installation.

, can place 

restrictions on vegetation and building construction if it impedes on solar easements).

Roof Warranties

The requirements outlined in Appendix B require that roofs be designed to accommodate 

installations of solar PV systems and/or SWH systems. In light of this, it is important that roof 

warranties accommodate the ultimate installation of a solar system without the fear of a warranty 

being voided by the installation of a system. Jurisdictions adopting solar ready mandates may 

 19 Database of State Incentives for Renewables & Efficiency (DSIRE). Georgia: Solar Easements 

http://dsireusa.org/incentives/incentive.cfm?Incentive_Code=GA01R&re=1&ee=1. Accessed April 2011. 20 Database of State Incentives for Renewables & Efficiency (DSIRE). California: City of Sebastopol Solar Access 

http://dsireusa.org/incentives/incentive.cfm?Incentive_Code=CA33R&re=1&ee=1. Accessed April 2011.

*The Colorado law uses the term energy efficiency, which includes renewable energy like solar.

Session Laws of Colorado 2008, Second Regular Session, 66th General Assembly

Concerning the removal of restrictions on the use of energy efficiency* measures in 

connection with real property.

38-30-168. Unreasonable restrictions on renewable energy generation devices -

definitions. (1)(a) A covenant, restriction, or condition contained in any deed, contract, 

security instrument, or other instrument affecting the transfer or sale of, or any interest in, 

real property that effectively prohibits or restricts the installation or use of a renewable 

energy generation device is void and unenforceable.
13

want to consider including requirements that will ensure that roof warranties are compatible 

with, and not voided by, the proper installation of a solar system.

Sample of Solar Ready Requirements or Practices by Jurisdiction

Appendix C summarizes the jurisdictions that have adopted solar ready into existing legislation, 

codes, or ordinances. The DSIRE website was a primary source for these excerpted entries.

21

Data on the effectiveness of these different approaches to solar ready would be useful for other 

jurisdictions looking to adopt similar policies. While outside of the scope of this report, 

compiling information on participation, increased number of solar ready structures, and 

increased number of solar installations as a result of these policies would help jurisdictions 

choose the most appropriate policy for their area. Similarly, new policies put in place should 

consider how to evaluate the effectiveness of those policies in promoting solar ready and solar 

installations.

A 

few others were obtained through direct e-mail or telephone contact with various jurisdictions. 

Of the examples cited, most require measures related to PV and SHW systems. Technical 

requirements range from SHW stub-outs to full PV site/situational plans (see Tucson, Arizona).

It should be noted that there appear to be a number of jurisdictions where elements of solar ready 

are practiced, but not mandated (see the City of Boulder or Aspen/Pitkin County). 

Incentives

Incentives are a mechanism used by governments for the purpose of encouraging the use of 

technologies considered to have public benefits. These can be financial incentives that reduce the 

cost of clean energy technologies, which are typically advanced, higher-cost technologies. 

Examples of financial incentives include tax credits or deductions, rebates, and reduced interest

rates on loans. These increase access to clean energy technologies into broader markets. 

Alternatively, incentives can be non-financial, in which a benefit other than money is used to 

encourage the use of technologies. Examples of non-financial incentives are expedited permitting 

and “density bonuses,” which allow developers to increase the maximum allowable development 

on a property in exchange for acting in the public good.

22

Making incentives available could raise the profile of building solar ready as well as encourage 

developers to do so. Such incentives would need to be carefully structured. Creating financial 

incentives for solar ready buildings is complicated because the buildings result in a potential for 

clean energy development, not actual clean energy production. Therefore, calculating the 

expected public good resulting from solar ready development is challenging. Non-financial 

incentives may be more straightforward, as they result in little direct cost to the government, so 

justification for the implementation of the incentive may be more politically palatable. 

While both types of incentives could be 

used to promote solar ready building, neither is currently used to do so. A literature review found 

no current incentives for solar ready construction. 

 21 Database of State Incentives for Renewables & Efficiency (DSIRE). See “State Incentives/Policies for Solar.”

www.dsireusa.org/solar/. 22 University of Wisconsin Center for Land Use Education. 2005. “Planning Implementation Tools: Density Bonus.” 

www.uwsp.edu/cnr/landcenter/pdffiles/implementation/densitybonus.pdf. Accessed April 2011.
14

Conclusion

Legislating solar ready construction is one method for promoting solar energy deployment. As 

opposed to the other methods discussed next, this method effectively requires developers to 

consider solar ready design. Pursuing solar ready through legislation should take into account a 

diverse group of stakeholders. Combined with training and educational tools, solar ready 

legislation could effectively increase solar ready design practices. Other methods for 

implementing solar ready may prove faster to initiate and offer more flexibility to stakeholders.
15

Solar Ready Certification

Certification Programs

This section discusses the use of certification programs as an option for advancing solar ready 

implementation. Solar ready certification could act as a standalone program or be integrated into 

existing programs such as ENERGY STAR and LEED. This section will discuss both 

approaches.

Solar Ready Certification’s Potential Benefits

In general, certification is used in green building to promote a standard and ensure desirable 

characteristics such as design, quality, environmental friendliness, safety, reliability, efficiency,

and interchangeability.

If it is not cost-effective or feasible to install solar at the time of construction or retrofit, creating 

a solar ready structure will save money and time when solar is pursued at a later date. This would 

eliminate barriers to future solar applications and facilitate market growth. In addition, certifying 

a building or home as solar ready helps the building owner advertise solar ready status and 

signifies the potential of the structure to take advantage of solar technologies later in the 

building’s life. Lastly, it helps raise awareness among property owners who may otherwise not 

have considered solar from the outset.

To summarize the potential benefits, certification of solar ready:

• Ensures a certain level of quality. Currently, any property could be advertised as solar 

ready, but the lack of a standard definition or technical requirements prevents this 

claim from carrying any weight.

• Signifies the opportunity to take advantage of changing electricity and solar markets.

• Allows building owners an easy avenue for advertising the status of their properties

or homes.

• Provides a measurable metric.

• Is voluntary and may be more palatable to building owners or developers than 

legislation.

• Can serve as a form of communication, awareness, and education on solar.

• May promote solar ready as a catalyst for market expansion by overcoming barriers 

that prevent solar projects from going forward. 

Challenges of Solar Ready Certification

One of the clear disadvantages of a solar ready certification program is that it does not guarantee 

installation of solar systems. If this becomes the norm, then the perceived value of solar ready 

programs could be diminished. Furthermore, solar ready itself does not reduce energy use or 

replace conventional energy with green energy, which raises the question as to whether solar 

ready should even be rewarded with a certification. 
16

When certification schemes are adopted, they regularly cite statistics regarding improved

standards, benefits, and financial savings. Yet, sometimes they can fail to reach their potential. 

For certification schemes to work, they require proper design and management to achieve the 

intended results.

23

A Solar Ready Certification Label

Similar to the ENERGY STAR or LEED label, guidelines could be established for achieving a 

solar ready label that stands separate from these existing programs.

24

There are several advantages of a standalone solar ready label that is specific to the achievement 

of being solar ready. If solar ready is incorporated into a more comprehensive green building 

program, making a structure solar ready would likely be one of several choices of green building 

measures one could choose from to obtain certification. This could inherently dilute the number 

of structures that become solar ready. A solar ready label would only be applied to buildings that 

were indeed solar ready. Furthermore, a standalone solar ready label would be positioned to gain 

brand recognition, raising awareness about solar installations and solar ready buildings. This 

brand could be developed into a sticker or plaque that could be put on infrastructure such as 

electrical panels that have room for solar interconnection, conduit, or pipes to signify solar ready 

status to future users.

An easy way to make sure a 

building is solar ready would be to find out if it has been solar ready certified. This label could 

be government based like ENERGY STAR or nonprofit backed like LEED. Local jurisdictions 

could also consider creating a solar ready certification and label. Any building may be able to 

earn a solar ready certification label if the building meets the established requirements.

A disadvantage of having solar ready as a standalone label as opposed to part of an existing 

certification program might be the more limited visibility and participation. However, it remains 

a good option for local jurisdictions or other entities wishing to emphasize the importance of 

solar ready. Additionally, too many certifications and label programs for this sector could 

complicate the market to the point where the solar ready label has little value.

Solar Ready Certification Status

ENERGY STAR

From a review of existing solar ready initiatives, there does not appear to be a certification 

program dedicated exclusively to solar ready practices in the United States. However, at this 

writing, actions have been taken to incorporate solar ready into ENERGY STAR and LEED 

certification programs.

ENERGY STAR is a DOE and EPA program focusing on improving energy performance in 

buildings as a method of reducing greenhouse gas emissions. ENERGY STAR recognition is 

available as an indicator of superior energy performance. Projects can alternatively achieve 

Designed to Earn ENERGY STAR to recognize architects’ intent that buildings operate at 

 23 Peters, Katherine McIntire. “ENERGY STAR Program Comes Under Attack.” March 30, 2010.

http://www.govexec.com/dailyfed/0310/033010kp1.htm. Accessed April 2011. 24 ENERGY STAR. “Apply for the ENERGY STAR for Your Buildings.”

http://www.energystar.gov/index.cfm?c=evaluate_performance.bus_portfoliomanager_intro. Accessed April 2011.
17

superior energy efficiency when built. Once the buildings are occupied and operating, they can 

earn the ENERGY STAR label.

25

The EPA has developed renewable energy ready home specifications to incorporate into the 

ENERGY STAR Concept Home Version 4 program requirements (ENERGY STAR Version 3 

will be fully adopted as the mandatory base program guidelines by January 1, 2012, followed by 

Version 4).

26 The content of Version 4 was rolled out before 2012, but it will be an optional 

guideline until it is completely phased into the program, replacing Version 3 (date of complete 

phase-in to be determined).27

In early 2012, the EPA plans to pre-release the renewable energy ready home specifications as an 

educational resource and to provide the opportunity for the ENERGY STAR builder community 

to give feedback. During the pre-release period, homes meeting the renewable energy ready 

specification would not be eligible as renewable energy ready homes for recognition under any

ENERGY STAR program guidelines.

Currently, PV and solar thermal are the only two technologies 

addressed by the renewable ready home specifications.

By incorporating renewable energy ready homes into ENERGY STAR, the EPA is maintaining a 

focus on energy efficiency while rewarding homes that are prepared to take the next step to solar 

energy. EPA designers of the solar ready guidelines see a large opportunity to educate both the 

home building community and homeowners through the solar ready addition. Homebuilders can

learn simple design and building practices that make a home solar ready. Upon receiving 

information about their solar ready home, homeowners can then learn about the opportunity to 

install solar systems.

In the ENERGY STAR renewable energy ready home checklist, applicants will have to meet a 

number of requirements in the following categorical areas:

• Building Array/Site Assessment 

• Structural and Safety Considerations: Photovoltaic (PV) or Solar Hot Water (SHW)

• Renewable Energy Ready Home Infrastructure

• Homeowner Education.

LEED

The Leadership in Energy and Environmental Design (LEED) Green Building Rating System is 

a green building certification offered by the nonprofit U.S. Green Building Council (USGBC).

28

 25 ENERGY STAR. “Design to Achieve Energy Star.”

LEED is a building certification process that looks at various aspects of green building and gives 

recognition to structures that meet certain standards. LEED has recently developed a draft titled

“EA Credit: Solar Ready Design” as part of its Homes Rating System with the designated intent 

http://www.energystar.gov/index.cfm?c=cbd_guidebook.cbd_guidebook. Accessed April 2011. 26ENERGY STAR. “Renewable Energy Ready Homes (RERH).”

http://www.energystar.gov/index.cfm?c=rerh.rerh_index. Accessed December 2011. 27 ENERGY STAR: ENERGY STAR for Homes Version 3 Guidelines.

http://www.energystar.gov/index.cfm?c=bldrs_lenders_raters.nh_v3_guidelines. Accessed April 2011. 28 U.S. Green Business Council. http://www.usgbc.org/DisplayPage.aspx?CMSPageID=283. Accessed April 2011.
18

to “reduce energy consumption and greenhouse gas emissions by designing to maximize 

opportunities for solar design.” 29

• Infrastructure requirements (hardware, raceway for PV, plumbing for SHW)

The draft emphasizes the following areas for solar ready 

design:

• Design approval by a PV or SHW contractor 

• Minimum roof space and orientation

• Informational material for occupant.

At this writing these draft changes to LEED Homes Rating System are in the public hearing 

phase and may be further modified before formally accepted into practice. A link to the 

document that was open for comment can be found at the USGBC website.

30

Conclusion

Both ENERGY STAR and LEED programs promote green building practices by offering a 

reward for incorporating specified characteristics into a building. The reward, or certification, 

offers a value to the owner for a variety of reasons. This may be from an increased market value 

of the property or the ability of the owner to meet federal or local mandates, or because the 

certification may serve as a symbol of environmental responsibility.

As opposed to mandating solar ready buildings through legislation, certification programs or 

guidelines encourage building owners to adopt solar ready practices by offering a reward or 

recognition. A drawback of incorporating solar ready into certification schemes is that it rewards 

building owners for building attributes that don’t reduce electricity consumption or generate 

green electricity. Nevertheless, a building stock of solar ready buildings would reduce 

installation barriers and likely increase solar production. Certification of solar ready buildings is 

a reasonable way to encourage solar ready design.

 29 LEED Rating System Draft. November 2010. www.usgbc.org/ShowFile.aspx?DocumentID=8186. Accessed April 

2011 (This draft is no longer available to the public). 30 U.S. Green Building Council. http://www.usgbc.org/. Accessed April 2011.
19

Stakeholder Education and Communication Methods

Stakeholder education represents a critical component of expanding the implementation of solar 

ready building practices. Whether in conjunction with solar ready legislation or certification 

programs, or as a standalone entity, education around solar ready is important to promoting 

widespread solar ready buildings. Solar ready buildings themselves further serve as conduits for 

solar education. This section explores multiple approaches to providing solar ready education.

Audience

Owners and real estate developers are the stakeholder groups most likely to benefit from a solar 

ready home or building. An owner with a solar ready home is positioned to take advantage of 

falling prices of solar technologies. At some point in the future, an owner can install a solar array 

to hedge against rising electricity prices. Likewise, real estate developers can advertise solar 

ready homes as a green investment in the future. Owners and developers ultimately decide how a 

building is designed and built. Education programs should emphasize the merits of equipping a 

house for solar at the time of construction as a best practice. However, in situations when solar 

installation at the time of construction is not feasible or is cost prohibitive, solar ready should be 

presented as the next best option.

Engineers and architects must understand the simple principles of solar ready design. Often, 

these principles can be applied without changing the cost or quality of the building design and 

should be considered good building practices. Solar ready is an added-value feature that

engineers and architects can offer owners in their design that requires little up-front cost.

Furthermore, knowledge of solar ready principles prepares architects and engineers to design 

buildings that meet mandates or certification requirements.

Methods of Delivering Education

Considering the large number of homes built in the United States each year, solar ready 

education of key stakeholders could have a significant impact on the future of solar in this 

country. Education and communication strategies must reach a large number of people in diverse 

fields. The discussion below explores several methods for reaching target audiences. Local 

governments, federal agencies, or nonprofit organizations could implement these methods.

Education Combined with Legislation or Policy

A strong approach for promoting solar ready is the combination of solar ready policy with an 

educational campaign. In this approach, the mandate requires developers, architects, and 

engineers to consider solar ready, while the educational campaign ensures they understand the 

best practices. Pairing education with a mandate motivates stakeholders to participate in 

education or training programs or to use available educational tools. Designing an education 

program in parallel to developing mandates may also help make mandates more palatable to the 

groups most affected.
20

Solar Ready Training – Boston, Massachusetts

The City of Boston’s Department of Neighborhood Development (DND) 31 has developed 

design standards for new construction and the rehabilitation of existing buildings. These 

ensure that all projects conform to current applicable regulations and promote cost effective, 

environmentally responsible quality design. DND requires that applicants for subsidized 

funding for building development be solar ready. DND has worked with the Solar Boston 

Initiative to incorporate solar into the housing portfolio through the Green Affordable 

Housing Program (GAHP). In conjunction with the solar ready requirement, the Green 

Affordable Housing Program offers specialized training sessions on Integrated Design and 

Renewable Energy and Energy Efficiency to help developers meet the solar ready and other 

green building requirements.

Education Combined with Certification

A certification program promotes solar ready building practices by offering a label or certificate 

and accompanying educational aspects. These aspects may include training programs, robust 

websites, and public awareness campaigns.

The EPA and USGBC have both had success promoting their respective certification programs,

ENERGY STAR and LEED. USGBC has a robust education program that parallels their 

certification program. Education is designed for those who are implementing LEED projects or 

seeking LEED certification.

USGBC provides a curriculum that is taught through a wide network of education providers.

Through this infrastructure, USGBC is able to offer hundreds of courses worldwide. Achieving 

LEED certification requires an educated workforce. In turn, USGBC provides training to the 

workforce that completes LEED projects. The projects themselves then act as an educational 

opportunity to the public that works or lives in high-performance green buildings. In the LEED 

Home Rating System draft, providing information about solar ready to the occupant is required.

Likewise, the EPA has recognized the educational potential of introducing the renewable energy 

ready home concept into ENERGY STAR. Ultimately, the EPA plans to incorporate the 

renewable energy ready home into the ENERGY STAR Concept Home Version 4. Because the 

Concept Home Version 4 will likely not be available for several years, the EPA plans to prerelease the renewable energy ready homes standard. This allows it to be available as an 

educational tool and resource for ENERGY STAR builders while encouraging the community to 

provide feedback on the specifications.

While the EPA recognizes that it will be difficult to track how many renewable energy ready 

homes actually result in installed renewable energy projects, the program nonetheless serves as 

an opportunity to educate homeowners about renewable energy. Like ENERGY STAR or LEED, 

local or standalone solar ready certification programs or labels can be conduits for education and 

communication about solar ready. Incorporated in ENERGY STAR or LEED, solar ready will 

 31 City of Boston Department of Neighborhood Development (DND). 

www.cityofboston.gov/dnd/d_green_housing.asp. Accessed April 2011.
21

reach a wider audience. A potential drawback of this approach is the dilution of the concept by 

couching it with other green building measures. On the other hand, this emphasizes the 

importance of pursuing energy efficiency concepts in parallel with renewable energy.

Education Combined with Incentives

One approach may be to make educational training mandatory in order to receive an incentive or 

benefit. This benefit could be monetary, access to a streamlined process, or eligibility for a 

certification.

Stakeholder Education

Appendix A lists organizations that can act as conduits for educating the stakeholders on solar 

ready construction. These organizations often sponsor conferences, workshops, robust websites, 

and newsletters, and many have a database of stakeholders. Promoting solar ready concepts 

through these organizations may be an effective way to reach front-end decision makers who can 

pave the way for solar development.

Guidelines

Some jurisdictions have taken an approach to promoting solar ready that neither mandates 

compliance nor rewards participants with a label or certification. Solar ready guidelines fall into 

this third category. Solar ready guidelines offer specific information and even specifications that 

can be used to educate stakeholders about solar ready and aid stakeholders in implementation.

Solar ready guidelines provide the information needed to construct solar ready buildings for 

those who are self-motivated to do so. When promoted by a visible entity or program, guidelines

can encourage stakeholders to consider building solar ready when they might not have 

otherwise.32 Likewise, the Twin Cities of Minneapolis and St. Paul, Minnesota, have pursued a 

solar ready building program based on location-specific guidelines and specifications.

 32 As technical assistance to the City of Boston, NREL designed solar ready guidelines that the city can use as an 

educational document to inform stakeholders. See Solar Ready Buildings Planning Guide, 

http://www.nrel.gov/docs/fy10osti/46078.pdf.
22

Solar Ready Guidelines – The Twin Cities, Minnesota33

The Twin Cities, Minnesota, have released two location-specific documents for use by public 

agencies, community organizations, the nonprofit and for-profit development communities,

and owners, architects, builders, and contractors. The Solar Ready Building Design 

Guidelines explain solar ready and outline guidance for designing and building a solar ready 

structure. The Solar Ready Construction Specification provides an implementation 

methodology for achieving solar ready buildings. The guidelines, released by the Twin Cities 

Solar America Cities Program in 2010, “ ... address specific site planning, building form, 

space planning, roofing, and mechanical and electrical issues to be considered in the design 

of solar ready buildings.” The accompanying specification document “ ... establishes 

responsibilities and procedures for implementing these requirements during the construction 

phase of the building process.” Both of these documents represent comprehensive education 

on solar ready building principles for a targeted audience in a targeted location. Supported by 

the city through the Solar America Cities Initiative, these documents will help overcome

“major barriers to the installation of solar energy systems [which] is the traditional design of 

[the] building stock” in the Twin Cities.

 33 Lunning Wende Associates, Inc. Solar Ready Building Design Guidelines for the Twin Cities, Minnesota.

September 2010.

www.state.mn.us/mn/externalDocs/Commerce/Solar_Ready_Building_Design_Guidelines_020211042659_SolarBu

ildingDesignGuidelines.pdf. Accessed April 2011.
23

Conclusion

Solar ready itself does not reduce energy use or create clean energy. Nevertheless, solar ready 

building practices are needed to reach the full potential of solar deployment. Without forethought 

on incorporating solar into design, buildings may be incompatible with solar due to roof structure 

or excessive shading. In these cases, retrofitting the roof or removing shading elements is cost 

prohibitive. Furthermore, higher up-front costs due to structural adaptations and production 

losses caused by less than optimal roof orientation, roof equipment, or shading will lengthen 

payback periods, making solar more expensive. With millions of new buildings constructed each 

year in the United States, solar ready can remove installation barriers and increase the potential

for widespread solar adoption.

There are many approaches to promoting solar ready, including solar ready legislation, 

certification programs, and education of stakeholders. Federal, state, and local governments have 

the potential to implement programs that encourage solar ready and in turn reduce barriers to 

solar deployment. With the guidance in this document and the examples of jurisdictions and 

organizations already working to promote solar ready building practices, federal, state, and local 

governments can guide the market toward solar ready implementation.
24

Appendix A – Trade Organization Resources

American Institute of Architects (AIA)

The AIA Board of Directors recognizes the need to prepare their members to 

respond to the challenge and opportunity facing the profession in environmentally 

responsible projects. The AIA offers a number of forums and programs by which 

industry professionals can learn about the latest developments. The AIA offers a 

continuing education program dedicated to sustainability in which solar ready 

modules may be incorporated.

American Solar Energy Society (ASES)

The American Solar Energy Society provides a conduit to integrate solar ready 

into solar energy education and communication. While the membership is often 

focused on solar installation, an additional emphasis on solar ready helps ensure 

that opportunities to make buildings solar ready will be cost effective into the 

future.

National Association for Industrial and Office Properties (NAIOP)

NAIOP, the Commercial Real Estate Development Association, is the leading 

organization for developers, owners, and related professionals in office, industrial,

and mixed-use real estate. NAIOP provides industry networking and education, 

and advocates for effective legislation on behalf of its members. NAIOP advances 

responsible, sustainable development that creates jobs and benefits the 

communities in which members work and live. The NAIOP Center for Education 

is the principal learning resource for the commercial real estate professional. It is 

organized as a system of continuing education, which includes webinars, courses, 

certificate programs, and chapter education partnership.

National Association of Home Builders (NAHB)

The National Association of Home Builders (NAHB) is one of the largest trade 

associations in the United States, with more than 800 state and local associations. 

About one-third of NAHB’s more than 175,000 members are home builders 

and/or remodelers. The home builder members of NAHB construct approximately 

80% of new homes each year in the United States. The various NAHB groups 

analyze policy issues and economic and consumer trends as well as educate and 

communicate industry news to the public. The NAHB organizes the International 

Builders’ Show, which is one of the largest conventions in North America for the 

residential and light commercial construction industry. NAHB publishes Nation’s 

Building News, a free weekly e-newspaper distributed to nearly 200,000 

recipients. The NAHB hosts educational seminars at the International Builders’

Show, which offered 900 courses to 6,000 conference participants in 2008.
25

U.S. Green Building Council (USGBC)

The USGBC has diverse resources and multiple formats for LEED and green 

building education and knowledge. Solar ready could potentially be adapted 

within existing programs. The USGBC offers a number of educational forums,

including: 

• USGBC’s LEED curriculum and workshops

• Reference guides

• Study guides

• Podcasts

• USGBC live chats

• Private LEED workshops.
26

Appendix B – Sample Solar Ready Legislation

1. Definitions – As used in the [name of act or chapter

A. “New Construction” includes any newly constructed residential or commercial 

building that requires a building permit to proceed. 

], 

B. “Developer” means any person or company who constructs residential or 

commercial buildings.

C. “Department” means [name of state agency who will undertake tasks identified 

below

D. “Solar Energy System” means any system that uses solar energy to provide all or 

a portion of the electrical needs of a residential or commercial building.

].

E. “Solar Hot Water Heater” means any system that uses solar energy to heat water 

for use in a residential or commercial building.

F. “Substitute Renewable Energy System” means any system that uses renewable 

energy resources, including wind and geothermal heat, to provide for all or a 

portion of the electrical needs of a residential or commercial building.

G. “Substitute Renewable Hot Water System” means any system that uses renewable 

energy resources, including geothermal heat, to provide for all or a portion of the 

hot water needs of a residential or commercial building.

2. New Construction Shall be Built Solar Ready

All new construction shall be built to accommodate the installation of a solar energy 

system and solar hot water heater in accordance with regulations adopted by the 

Department and in accordance with the following sections. 

3. Solar Energy System Readiness Standards

A. The Department shall promulgate regulations by [date

B. In drafting the regulations, the Department shall take into account existing 

building code requirements and compliance costs. The Department shall also 

consult with scientists, engineers, professional societies, and government agencies 

with relevant expertise in solar energy systems and building construction.

] that establish minimum 

standards that must be met for new construction to accommodate a solar energy 

system.

C. At a minimum, the Department shall include requirements for:

i. Static load roof strength, with a requirement that roofing where solar 

equipment could be placed be capable of supporting a minimum of 6 

lb/ft2

;
27

ii. Placement of non-solar related rooftop equipment, taking into account 

positioning that avoids shading of solar equipment and maximization of 

continuous roof space;34

iii. Sizing and/or provision of extra electrical panels to accommodate addition 

of an appropriately sized future solar energy system; 35

iv. Provision of space for a solar energy system DC-AC inverter in the utility 

room or on an outside wall.

and

D. The Department shall also consider including requirements for:

i. Roof orientation and angle;36

ii. Roof types that are compatible with a solar installation mounting strategy 

that will require minimal or no roof penetrations;37

iii. A conduit for wiring from roof to electric panel.

and

E. To the extent necessary, the Department shall promulgate separate standards for 

residential and commercial construction.

4. Solar Hot Water Heater Readiness Standards

A. The Department shall promulgate regulations by [date]

B. In drafting the regulations, the Department shall take into account existing 

building code requirements and compliance costs. The Department shall also 

consult with scientists, engineers, professional societies, and government agencies 

with relevant expertise in solar hot water heating and building construction.

that establish minimum 

standards that must be met for new construction to accommodate a solar hot water 

heater.

C. At a minimum, the Department shall include requirements for:

i. Roof strength, with a requirement that roofing where solar hot water 

heating equipment could be placed be capable of supporting a minimum of 

6 lb/ft2

;

ii. Placement of non-solar-related rooftop equipment, taking into account 

positioning that avoids shading of solar equipment and maximization of 

continuous roof space;38

 34 To optimize future solar energy and hot water systems, NREL recommends that there be at least 75% continuous 

roof space, unobstructed by HVAC equipment, vents, or any other objects, and that all such equipment be located on 

the north end of the solar ready roof. www.nrel.gov/docs/fy10osti/46078.pdf. Accessed April 2011. 35 To optimize future solar energy and hot water systems, NREL recommends that residential electrical panels have 

an excess of 30% capacity and that space for an additional electric panel be provided in commercial buildings. 

www.nrel.gov/docs/fy10osti/46078.pdf. Accessed April 2011. 36 To optimize future solar energy and hot water systems, NREL recommends that all buildings be oriented with a 

sky view within 15 feet of due south or be flat in order to be considered solar ready. 

www.nrel.gov/docs/fy10osti/46078.pdf. Accessed April 2011. 37 To optimize future solar energy and hot water systems, for flat roofs NREL recommends fully adhered 

thermoplastic olefin or polyolefin (TPO) roofing. For slanted roofs, NREL recommends a structurally fastened 

standing seam roof. www.nrel.gov/docs/fy10osti/46078.pdf. Accessed April 2011.
28

iii. Provision of sufficient free space in utility rooms for solar hot water 

equipment at a minimum of one times the space required for the 

conventional water heating equipment;

iv. Plumbing that will allow solar hot water piping to be attached to a 

conventional system without requiring the building water system to be depressurized;

39

v. Plan hot water distribution systems to accommodate SHW system 

integration;

vi. On-demand water heaters that can operate in conjunction with a SHW 

system or implement distributed domestic hot water tanks that are capable 

of being integrated with a SHW system; and

vii. Roof types that are compatible with a solar installation mounting strategy 

that will require minimal or no roof penetrations.

40

D. The Department shall also consider including requirements for:

i. Plumbing installed from the utility room to the roof of the building and

ii. Metering of hot water load in commercial buildings.

E. To the extent necessary, the Department shall promulgate separate standards for 

residential and commercial construction.

5. Exemptions 

A. Developers may seek an exemption from [building code official or the 

Department

i. Accommodation of a solar energy system and/or a solar hot water heater 

would be impractical due to poor solar resources at a site of new 

construction;

] from the solar system and/or solar hot water heater readiness 

requirements upon a sufficient showing that:

ii. A substitute renewable energy system will be installed at the time of new 

construction; or

iii. A substitute renewable hot water system will be installed at the time of 

new construction. 

B. The Department shall issue regulations that define what constitutes a sufficiently 

poor solar resource such that a building should be exempted. The Department 

shall also consider publishing a list of acceptable software tools that can be 

utilized to determine the available solar resources for a building.

 38 NREL recommends that there be at least 75% continuous roof space, unobstructed by HVAC equipment, vents, or

any other objects, and that all such equipment be located on the north end of the solar ready roof. 39 NREL recommends requiring that T-joints and shut-off valves be required to accomplish this purpose. 40 To optimize future solar energy and hot water systems, for flat roofs NREL recommends fully adhered 

thermoplastic olefin or polyolefin (TPO) roofing. For slanted roofs, NREL recommends a structurally fastened 

standing seam roof. www.nrel.gov/docs/fy10osti/46078.pdf. Accessed April 2011.
29

C. The Department shall publish regulations by [date

6. Availability of Incentives 

] that clearly define the process 

for seeking an exemption.

Compliance with the provisions of this [Act

7. Enforcement

] shall not impair a pre-existing building’s 

eligibility for any incentives, rebates, credits, or other programs in existence to 

encourage development of renewable resources.

A building permit for new construction may not be granted without a showing that the 

building complies with the requirements of this [Act].
30

City of Tucson Energy Office 

4004 S. Park Ave., Bldg. 1

Tucson, AZ 85714 

Bruce Plenk

Phone: 520-791-5111

Email: bruce.plenk@tucsonaz.gov

Website: http://cms3.tucsonaz.gov/energy

Database of State Incentives for 

Renewables and Efficiency: 

Arizona, City of Tucson – Solar Design 

Requirement for Homes 

http://www.dsireusa.org/incentives/incentive.c

fm?Incentive_Code=AZ26R&re=1&ee=1

Appendix C – Sample of Solar Ready Requirements or Practice 

by Jurisdiction

1 Arizona

1.1 Tucson – Solar Design Requirement for Homes

1.1.1 Type of Technology

The requirement addresses photovoltaic (PV) and solar water heating systems.

1.1.2 Legislative Mandate/Option

Tucson adopted an ordinance in June 2008 that

requires all new single-family homes and duplexes in 

Tucson to be solar ready. The ordinance requires all 

new homes either to have a PV and solar water heating 

system installed, or to have all the necessary hardware 

installed so that a system can easily be installed at a 

later date.

1.1.3 Technical Requirements

To comply with this requirement, new homes must 

either have a complete solar water heating system 

installed or comply with one of two solar stub-out 

options. Option one requires the installation of two 

insulated pipes and a suitably sized conduit (for two 

pairs of monitoring and control wires) that run from 

the water heater area through the roof and are capped. Option two does not require the 

installation of pipes, but it does require the installation of a sleeve or conduit of sufficient size to 

hold the two insulated pipes and wires. With option two there must be a straight line from the 

water heater area to the roof. Both options will greatly cut down on the cost of installing a 

system at a later date. To comply with the PV requirement, a site plan must indicate the best roof 

space for locating the PV panels, and provide a roof structure designed for the additional 

collector weight. The site plan must also illustrate the best space available for accommodating 

PV equipment (meter, inverter, disconnect), and it should be adjacent to the electrical service 

panel or on a wall near the proposed location of the panels. There must also be a minimum 

3,800-volt-ampere PV electrical load entry on the service load calculation, and an Electrical 

Panel Schedule with a 240-volt circuit breaker space labeled “reserved for photovoltaic.”

1.1.4 Agency Responsible for Specifications

The ordinance was developed by a stakeholder group that included Technicians for 

Sustainability, the Tucson Association of Realtors, the Sierra Club, the Southern Arizona 

Homebuilders Association, architectural professionals, solar energy companies, and elements of 

the city government.
31

1.1.5 Exceptions

These requirements may be waived if it can be demonstrated to the building official that 

compliance is not practical due to shading, building orientation, construction constraints, or the 

configuration of the parcel of land.
32

2 California

2.1 California State Energy Code

2.1.1 Type of Technology

The requirement addresses PV and solar water heating systems.

2.1.2 Legislative Mandate/Option

California Green Building Standards Code (GBSC)

(Title 24, Part 11). On page 60 (page 69 of the .pdf), 

there are residential voluntary measures for “space for 

future solar installation” (A4.211.3) and “future access 

for solar system” (A4.211.4).

2.1.3 Technical Requirements

On page 127 (page 136 of the .pdf), there are 

nonresidential voluntary measures for “prewiring for 

future solar” (A5.211.4) and “off-grid prewiring for 

future solar” (A5.211.4.1). Local jurisdictions may 

make portions of the GBSC mandatory, but there are no specifics. To view the text of the local 

ordinances go to:www.energy.ca.gov/title24/2008standards/ordinances/. Note that these local 

ordinances are primarily meant to exceed the California Energy Code (Title 24, Part 6) but may 

also contain additional elements, such as those from the GBSC.

2.2 Marin County – Single-Family Dwelling Energy Efficiency Ordinance

2.2.1 Type of Technology

The requirement addresses PV and solar water heating 

systems.

2.2.2 Legislative Mandate/Option

Marin County Code 19.04.100.

2.2.3 Technical Requirements

New commercial buildings over 5,000 square feet and 

all new residential construction must include plumbing 

and electrical conduit specifically designed to 

accommodate the easy installation of solar water 

heaters and PV systems in the future. These systems 

can be used to comply with the building code, but they 

are not required by the building code.

2.2.4 Agency Responsible for Specifications

The exact requirements for these solar ready additions will be adopted by the chief building 

inspector.

California Energy Commission

Patrick Saxton

Phone: 916-651-0589

Email: psaxton@energy.state.ca.us

Database of State Incentives for 

Renewables and Efficiency: 

California State Energy Code

http://www.dsireusa.org/incentives/incentive.

cfm?Incentive_Code=CA51R&re=1&ee=1

Marin County Community Development 

Agency

3501 Civic Center Dr. #308 

San Rafael, CA 94903-4157

Omar Pena

Phone: 415-507-2797

Website: 

http://www.co.marin.ca.us/depts/CD/main/co

mdev/ADVANCE/index.cfm

Database of State Incentives for 

Renewables and Efficiency: 

Marin County – Green Building 

Requirements

http://www.dsireusa.org/incentives/incentive.

cfm?Incentive_Code=CA40R&re=1&ee=1
33

3 Colorado

3.1 Colorado Building Energy Code with Mandatory Solar Option

3.1.1 Type of Technology

The requirement addresses PV and solar water heating 

systems.

3.1.2 Legislative Mandate/Option

HB 1149, enacted in May 2009, requires builders of 

single-family homes to offer solar as a standard feature 

to all prospective homebuyers. 

3.1.3 Technical Requirements

Builders are required to give the buyer the option to 

either have a PV system or a solar water heating 

system installed on their new home, or to have all the 

necessary wiring and/or plumbing installed so they can 

easily add a solar system at a later date. The builder 

must also provide the buyer with a list, maintained by 

the Governor's Energy Office, of every solar installer in the area, so the buyer can obtain expert 

help in determining if their home's location is suitable for solar and what the estimated cost 

savings would be.

3.2 Boulder Green Points Building Program

3.2.1 Type of Technology

The requirement addresses PV and solar water heating 

systems.

3.2.2 Legislative Mandate/Option

There is no code or ordinance. But on page 127 (page 

136 of the .pdf), there are nonresidential voluntary 

measures for “prewiring for future solar” (A5.211.4) 

and "off-grid prewiring for future solar" (A5.211.4.1).

Governor's Energy Office

1580 Logan Street, Suite 100

Denver, CO 80203

James Dillon

Phone: 303-866-2100

Fax: 303-866-2930 

E-Mail: jamil.dillon@state.co.us

Database of State Incentives for 

Renewables and Efficiency: 

Colorado Building Energy Code with 

Mandatory Solar Option

http://www.dsireusa.org/incentives/incentive.

cfm?Incentive_Code=CO36R&re=1&ee=1

City of Boulder, Department of 

Community Planning & Sustainability 

Brian Holmes

Zoning Administrator

Phone: 303-441-3212

Fax: 303-441-3241

Email: HolmesB@bouldercolorado.gov

Database of State Incentives for 

Renewables and Efficiency: 

City of Boulder – Green Points Building 

Program

http://www.dsireusa.org/incentives/incentive.

cfm?Incentive_Code=CO06R&re=1&ee=1
34

3.3 Aspen & Pitkin County – Renewable Energy Mitigation Program

3.3.1 Type of Technology

The requirement addresses solar water heat, PV, and 

geothermal heat pumps.

3.3.1.1 Legislative Mandate/Option

Pitkin County does not require homes to be solar 

ready. It does, however, have a mandatory Efficient 

Building Program (EBP) that requires residences to 

score points by incorporating sustainable building 

measures in home construction. Solar ready measures 

are one of the ways the builder may choose to score 

points. The EBP is mandatory—a building permit 

cannot be issued without scoring enough points. To

summarize, some homes in unincorporated Pitkin 

County are solar ready, but the percentage is very low.

Pitkin County 

Tony Fusaro

Chief Building Official

Phone: 970-920-5101

Website: www.aspenpitkin.com

Database of State Incentives for 

Renewables and Efficiency: 

Aspen & Pitkin County – Renewable Energy 

Mitigation Program

http://www.dsireusa.org/incentives/incentive.

cfm?Incentive_Code=CO16R&re=1&ee=1
35

4 Guam

4.1 Guam – Solar Ready Residential Building Requirement

4.1.1 Type of Technology

The requirement addresses solar hot water heaters.

4.1.1.1 Legislative Mandate/Option

The Guam Energy Code became effective in October 

2000.

4.1.2 Technical Requirements

The requirement mandates that piping stub-outs be 

provided for water heaters installed in low-rise 

residential buildings to enable the future installation of 

solar collectors.

Guam Energy Office 

Pacific Energy Resources Center

548 N. Marine Drive 

Tamunung, GU 96911

Lorilee Chrisostomo

Phone: 617-646-4361

Fax: 671-649-1215

Email: lorilee@guamcell.net

Website: www.guamenergy.com

Database of State Incentives for 

Renewables and Efficiency: 

Guam – Solar-Ready Residential Building 

Requirement

http://www.dsireusa.org/incentives/incentive.

cfm?Incentive_Code=GU01R&re=1&ee=1
36

5 New Jersey

5.1 New Jersey Solar Energy Option Requirement for Residential Developments

5.1.1 Type of Technology

Broad definition could include passive as well as active solar elements.

5.1.1.1 Legislative Mandate/Option

In March 2009, New Jersey enacted legislation 

designed to support the integration of solar energy 

systems into new residential developments. The law 

requires that, whenever “technically feasible,”

developers of residential developments with 25 or 

more dwelling units (i.e., single-family residences) 

offer to install or provide for the installation of a solar 

energy system on the unit during negotiations with a 

prospective purchaser. Developers are required to 

disclose this option in their advertising materials, 

which must include information on installation costs, 

environmental benefits, energy cost savings, and 

incentive programs for which the installation may 

qualify.

5.1.2 Technical Requirements

NJ // P.L. 2009, CHAPTER 33 / 3 stipulates that the 

solar energy system is to be installed in conformance 

with the manufacturer's specifications and in compliance with all applicable electrical and 

building code standards.

5.1.3 Agency Responsible for Specifications

The Board of Public Utilities shall adopt orders, rules, or regulations that provide for solar 

energy systems installed in accordance with the provisions of P.L. 2009, c.33.

New Jersey Department of Community 

Affairs

101 South Broad St.

PO Box 802

Trenton, NJ 08625-0802

Darren Port

Division of Codes and Standards

Phone: 609-984-7607

Website: 

http://www.state.nj.us/dca/divisions/codes/in

dex.html 

Database of State Incentives for 

Renewables and Efficiency: 

New Jersey Solar Energy Option 

Requirement for Residential Developments

http://www.dsireusa.org/incentives/incentive.

cfm?Incentive_Code=NJ18R&re=1&ee=1
37

6 Massachusetts

6.1 City of Boston

6.1.1 Type of Technology

The requirement addresses PV systems.

6.1.1.1 Legislative Mandate/Option

The City of Boston Department of Neighborhood 

Development (DND) coordinates the construction of 

affordable housing units within the city. DND has 

worked with the Solar Boston Initiative to incorporate 

solar into the department housing portfolio through the 

Green Affordable Housing Program (GAHP) as part of 

a $1.8 million grant from the Massachusetts Clean 

Energy Center. The DND has required that all future affordable housing development in the city 

be built to solar ready guidelines.

6.1.2 Technical Requirements

The solar ready guidelines, which were developed with the help of NREL, require new 

affordable housing developments to limit roof obstructions and to avoid roof designs that would 

complicate future solar installations. The solar ready standard has been in place since 2007 for all 

DND-developed affordable housing projects.

City of Boston

Andrew Belden

Department of Neighborhood 

Development

Email: Andy.Belden@mc-group.com