A national laboratory of the U.S. Department of Energy

Office of Energy Efficiency & Renewable Energy

National Renewable Energy Laboratory 

Innovation for Our Energy Future 

Energy Savings Modeling and 

Inspection Guidelines for 

Commercial Building Federal 

Tax Deductions 

Second Edition 

M. Deru 

Technical Report 

NREL/TP-550-40467 

May 2007 

NREL is operated by Midwest Research Institute ● Battelle Contract No. DE-AC36-99-GO10337 
National Renewable Energy Laboratory

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Operated for the U.S. Department of Energy 

Office of Energy Efficiency and Renewable Energy 

by Midwest Research Institute • Battelle 

Contract No. DE-AC36-99-GO10337

Technical Report 

NREL/TP-550-40467 

May 2007 

Energy Savings Modeling and 

Inspection Guidelines for 

Commercial Building Federal 

Tax Deductions 

Second Edition 

M. Deru 

Prepared under Task No. BEC6.2001 
NOTICE

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Acknowledgments 

This work was funded through the U.S. Department of Energy Building Technologies Program. The 

author would like to thank the following individuals for reviewing this document: Drury Crawley of 

DOE; Ron Judkoff, Paul Torcellini, Dennis Barley, Brent Griffith, Shanti Pless, and Otto VanGeet of 

NREL; Jennifer Bernardini of the Internal Revenue Service; and Philip Fairey and Muthusamy Swami of 

the Florida Solar Energy Center. 

 iii 
Contents 

Acknowledgments........................................................................................................................................iii

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

2 Guidelines for the Interim Lighting Rule.............................................................................................2

3 Energy Modeling Guidelines ...............................................................................................................2

3.1 Calculating the Energy and Power Cost Savings ........................................................................3

3.2 Software Requirements................................................................................................................4

3.3 Weather Data ...............................................................................................................................5

3.4 Building Model Parameters.........................................................................................................5

3.5 Internal Loads and Schedules......................................................................................................6

3.6 Use of Standard 90.1-2004 Appendix G .....................................................................................7

3.7 Model Documentation.................................................................................................................9

4 Inspection Guidelines.........................................................................................................................10

5 References..........................................................................................................................................11

Appendix A – Lighting System Compliance Form ....................................................................................13

Appendix B – 2005 California Nonresidential ACM Approval Manual Infiltration Modeling Rules .......15

Appendix C – 2005 California Nonresidential ACM Approval Manual Internal Loads and Schedules....16

Appendix D – 2005 California Nonresidential ACM Approval Manual Illuminance Categories and 

Luminaire Power.........................................................................................................................................26

 iv 
1 Introduction 

This document provides guidance for modeling and inspecting energy-efficient property in commercial 

buildings for certification of the energy and power cost savings related to § 179D of the Internal Revenue 

Code (IRC) enacted in § 1331 of the 2005 Energy Policy Act (EPAct 2005) and noted in Internal Revenue 

Service (IRS) Notice 2006-52. Specifically, § 179D provides federal tax deductions for energy-efficient 

property related to a commercial building’s envelope; interior lighting; heating, ventilating, and air 

conditioning (HVAC); and service hot water (SHW) systems. 

The qualification levels and tax deductions are summarized in Table 1. A fully qualifying property saves 

at least 50% in energy and power costs for improvements in the envelope, lighting, HVAC, and SHW 

systems compared to a reference building that meets the minimum requirements of 

ANSI/ASHRAE/IESNA Standard 90.1-2001 with addenda a, b, c, d, and k (Standard 90.1-2001) as 

defined in IRS Notice 2006-52. A partially qualifying property saves at least 162⁄3% in energy and power 

costs through efficiency improvements in any one of envelope, lighting, or HVAC and SHW. The energy 

and power cost savings are determined for the energy use in the interior lighting, HVAC, and SHW 

systems. In addition, the interim lighting rule provides for tax deductions based on reductions in the 

lighting power density (LPD). 

Additions to existing buildings or alterations to existing buildings can qualify for tax deductions in the 

new or retrofitted areas of the building only. The savings requirements are relative to a reference building 

that meets the minimum requirements of Standard 90.1-2001 and not relative to the performance of the 

existing building. 

The taxpayer must obtain certification of the savings from the energy-efficient property to qualify for the 

federal tax deductions. The certification requirements are defined in Section 4 of IRS Notice 2006-52. 

The certification process includes calculating the energy and power cost savings and inspection of the 

energy-efficient property by a qualified individual as defined in Notice 2006-52. The Performance Rating 

Method (PRM) from Appendix G of ANSI/ASHRAE/IESNA Standard 90.1-2004, with the additional 

guidance presented in Section 3 of this document, shall be used to compute the energy and power cost 

savings. Section 4 of this document provides guidance for the inspection of the energy-efficient property. 

Table 1 Summary of Tax Deductions 

Fully Partially Qualifying Property 

Qualifying 

Property Envelope HVAC and 

SHW 

Lighting Interim Lighting 

Rule 

Savings 

Requirements*

50% energy 

and power cost 

savings 

162⁄3% energy 

and power cost 

savings 

162⁄3% energy 

and power cost 

savings 

162⁄3% energy 

and power cost 

savings 

25% lower LPD (50% 

for warehouses) 

Tax Deduction Cost of 

qualifying 

property up to 

$1.80/ft2

Cost of 

qualifying 

property up to 

$0.60/ft2

Cost of qualifying 

property up to 

$0.60/ft2

Cost of qualifying 

property up to 

$0.60/ft2

Cost of qualifying 

property up to 

$0.60/ft2

 times 

applicable 

percentage** 

* Savings refer to the reduction in the energy and power costs of the combined energy for the interior lighting, 

HVAC, and SHW systems as compared to a reference building that meets the minimum requirements of Standard 

90.1-2001. 

** The tax deduction is prorated depending on the reduction in LPD. See IRS Notice 2006-52 for the definition of 

“applicable percentage.” 

 1 
2 Guidelines for the Interim Lighting Rule 

This section provides guidance for the tax deduction under the interim lighting rule in § 179D of the IRC. 

The interim rule states that the LPD must be reduced at least 25% (50% for warehouses) from the values 

in Standard 90.1-2001 Tables 9.3.1.1 or 9.3.1.2. The building area method or the space by space method 

can be used to determine the LPD reduction in accordance to Standard 90.1-2001 Section 9.3. Alterations 

to existing buildings must comply with the control requirements in Section 4.1.2.2.5 in Standard 90.1-

2001. The bi-level switching requirement from EPAct 2005 applies to both new and existing building 

projects. 

In order to qualify for the tax deduction, document the reduction in LPD for each building space, and 

conduct a physical inspection of the taxpayer’s building. The documentation may be completed any 

form, a spreadsheet, or other software that shows the Standard 90.1-2001 requirements and the reduced 

LPDs. The mandatory control and minimum illuminance requirements must be documented with a 

physical inspection of the taxpayer’s building following these steps: 

1. Document that the taxpayer’s building meets or exceeds the mandatory provisions of the Standard 

90.1-2001 using the Standard 90.1-2001 lighting compliance form or an equivalent form. For 

alterations to existing buildings, there may be an exception for the lighting controls according to 

Section 4.1.2.2.5 in Standard 90.1-2001. The Standard 90.1-2001 compliance forms can be 

downloaded from ASHRAE at www.ashrae.org/technology/page/97. 

2. Document the installed LPD on the Standard 90.1-2001 Lighting Compliance form or equivalent 

form and ensure that this is equal to or lower than the allowable LPD per Standard 90.1-2001. 

3. Document the IESNA minimum illuminance levels and measured illuminance levels in Table 

LF1 from Appendix A of this document or on an equivalent form. Record the average of 

measurements taken on the working surfaces or at the locations listed in the IESNA handbook. 

The measured average values must equal or exceed the IESNA recommended minimum 

illuminance levels. In addition, no more than 2.5% of the measurements may be below 1/3 of the 

IESNA recommended minimum illuminance levels. This latter requirement follows a normal 

distribution of data points, which assumes that two standard deviations from the measurements 

equal 1/3 of the recommended illuminance level. Measurements only need to be completed once 

for each unique space and lighting arrangement. 

4. Verify that the bi-level switching requirement under the interim rule for lighting systems is met in 

Table LF4 of Appendix A or on an equivalent form. 

3 Energy Modeling Guidelines 

For tax deductions not under the interim lighting rule, the energy and power cost savings of the taxpayer’s 

building are determined from annual hourly energy simulations of a Proposed Building model and a 

Reference Building model. Table 2 provides descriptions of the building models. The energy modeling 

must be completed in accordance with the PRM presented in ANSI/ASHRAE/IESNA Standard 90.1-2004 

Appendix G, but the models must comply with the requirements of Standard 90.1-2001. This section 

provides guidance for coordinating Standard 90.1-2004 Appendix G methodology with the efficiency 

requirements of Standard 90.1-2001. 

For additions or alterations to existing buildings, model just the portions of the building affected by the 

changes with appropriate models for connections to the unaltered portions of the building. The Reference 

Building model shall meet the minimum requirements of Standard 90.1-2001. 

 2 
Table 2 Building and Model Descriptions 

Building/ Model Description 

Taxpayer’s Building Physical building used for the tax deduction. 

Reference Building Model 

Computer simulation model that matches the Taxpayer’s Building except that the 

interior lighting systems, HVAC, SHW, and building envelope comply with the 

minimum requirements of Standard 90.1-2001. 

Proposed Building Model 

Computer simulation model that is identical to the Reference Building model 

except for the systems that are qualifying for the tax deduction. The systems 

qualifying for the tax deduction shall match the systems in the Taxpayer’s 

Building. This model may not represent the Taxpayer’s Building exactly for 

partially qualifying properties. 

3.1 Calculating the Energy and Power Cost Savings 

The energy and peak demand for the interior lighting, HVAC, and SHW systems, as calculated from the 

hourly annual energy simulations, is used to determine the energy and power cost savings. Receptacle, 

process, and other loads are included in the energy simulations, but the energy and power costs associated 

with these loads are not included in the savings calculation. Determining the power cost savings requires 

knowing the power consumption for the whole building and for the interior lighting, HVAC, and SHW 

systems at the time of the building peak demand for each month. Power costs are defined as the monthly 

peak demand charges and associated taxes and fees. 

To calculate the annual energy and power costs, you need to: 

• Use the same utility tariff for the Proposed Building and the Reference Building models. 

• Use the utility rate structure that applies to the taxpayer’s building or the state average 

commercial building utility rates published by the Energy Information Administration 

(www.eia.doe.gov/). If energy is provided to the building free of charge or the building does not 

have its own utility billing, use the utility tariffs that would apply if the building were billed 

independently. 

• Include all utility costs in the calculations. Monthly fixed fees should be divided between the 

energy and power cost totals, based on the ratio of these costs. 

• Do not include on-site renewable energy generation of electricity that is connected to the building 

electrical system in the energy simulations or in the energy and power cost calculations. 

• Solar hot water systems can be included as part of the HVAC or the SHW systems. However, if 

the solar hot water system was used for a different federal tax deduction, it cannot be used again 

for a tax deduction under § 179D of the IRC. 

• Calculate the energy and power costs as follows to include all the energy and demand charges 

that occur due to seasonal rates, ratcheting, block charges, time of use rates, or other pricing 

structures: 

1. Record the monthly energy and peak electricity demand values for the entire building and the 

monthly energy values for the sum of the interior lighting, HVAC, and SHW systems for the 

Proposed Building and the Reference Building models (Ei, j, Di, j and ei, j). The monthly peak 

demand for the interior lighting, HVAC, and SHW systems shall be from the same time as 

the building peak demand. 

2. Record the monthly energy and power costs for each type of delivered energy for the 

Proposed Building and the Reference Building models (Ci, j). Or calculate these numbers 

from the energy and peak demand values from the energy simulations. 

3. Calculate the monthly energy costs for the interior lighting, HVAC, and SHW systems based 

on the fraction of the total building energy by energy type (electricity, gas, etc.) used by these 

 3 
systems, as shown in Equation 1 for the Proposed Building and Reference Building models 

(ci, j). 

4. Calculate the combined monthly demand costs for the interior lighting, HVAC, and SHW 

systems based on the fraction of the total building peak demand used by these systems, as 

shown in Equation 2 for the Proposed Building and the Reference Building models (di, j). 

5. Calculate the annual energy and power costs for the Proposed Building and Reference 

Building models for the interior lighting, HVAC, and SHW systems by summing the monthly 

energy and power costs, as shown in Equation 3 (Up and Ur). Calculate the energy and power 

costs for the Reference Building model as the average of the annual energy and power costs 

from the four simulations. 

6. Use Equation 4 to calculate the annual energy and power cost savings for the interior lighting, 

HVAC, and SHW systems (S). 

j,i

j,i

j,i

j,i C

E

e

c = (1) 

j,i

j,i

j,i

j,i D

P

p d

i

= (2) 

= ∑∑( + )

i j

j,ij,i dcU (3) 

rpr

×−= 100U)UU(S (4) 

Where: 

ci, j energy cost for the lighting, HVAC, and SHW systems for energy type i and month j 

Ci, j total energy cost for the building for energy type i and month j 

di, j peak demand cost for the lighting, HVAC, and SHW systems for energy type i and month j 

Di, j total peak demand costs for the building for energy type i and month j 

ei, j energy use for the lighting, HVAC, and SHW systems for energy type i and month j 

Ei, j total energy use for the building for energy type i and month j 

pi, j peak demand for the lighting, HVAC, and SHW systems for energy type i and month j 

coincident with the building peak demand 

Pi, j total peak demand for the building for energy type i and month j 

S annual percent energy and power cost savings for the interior lighting, HVAC, and SHW 

systems 

Up annual energy and power costs of the interior lighting, HVAC, and SHW systems for the 

Proposed Building model 

Ur annual energy and power costs of the interior lighting, HVAC, and SHW systems for the 

Reference Building model 

3.2 Software Requirements 

The same software and version number must be used to model the Reference Building and the Proposed 

Building, and the software must be included (at the time the certification is given) on the DOE published 

list of qualified software www.eere.energy.gov/buildings/info/qualified_software/. The list of qualified 

compliance software for use in the interim lighting rule and for showing model code compliance is also 

available on this Web site. 

 4 
3.3 Weather Data 

The energy simulations of the Reference Building and the Proposed Building models must use the same 

annual hourly weather file and the same design day weather conditions. The annual weather file must 

represent a typical weather year for the taxpayer’s building location. The weather file should be selected 

from the climate zone that most closely represents the typical weather conditions at the location of the 

taxpayer’s building. This may or may not be the weather file that is located closest to the taxpayer’s 

building. Many simulation programs provide specially formatted versions of the TMY2 or other similar 

weather files for use with their programs. Sources of typical weather year data files are listed in Table 3. 

Table 3 Annual Weather File Sources 

Weather File Source 

TMY2 – Typical Meteorological Year 2 rredc.nrel.gov/solar/old_data/nsrdb/tmy2/

CTZ2 – California Climate Zone 2 www.energy.ca.gov/title24/index.html 

The design day weather data used for sizing equipment shall represent the 99.6% annual cumulative 

frequency dry-bulb temperature for heating conditions and the 1% annual cumulative frequency dry-bulb 

and wet-bulb temperatures for cooling conditions. Table 4 lists sources of design day weather data. 

Table 4 Design Day Weather Data Sources 

Weather File Source 

ANSI/ASHRAE Standard 169-2006 (ASHRAE 2006) 

ASHRAE Handbook of Fundamentals 2005 (ASHRAE 2005) 

3.4 Building Model Parameters 

As defined in Table 2, the Reference Building model represents the taxpayer’s building except that the 

envelope, interior lighting, HVAC, and SHW must comply with the minimum requirements of Standard 

90.1-2001; and the Proposed Building model is identical to the Reference Building model, except that the 

building systems used for the tax deduction must match the taxpayer’s building. Table 5 shows the main 

modeling parameters of the two buildings. 

 5 
Table 5 Summary of Building Modeling Parameters for a Fully Qualifying Building 

Parameter Reference Building Model Proposed Building Model 

Building/Space 

Classification 

Same as taxpayer’s building and in 

accordance with Standard 90.1-2001 § 

9.3.1.1 or 9.3.1.2 

Same as Reference Building model 

Location Same as taxpayer’s building Same as Reference Building model 

Utility Rate Structure Same as taxpayer’s building (see Section 

3.1) Same as Reference Building model 

Annual Weather Data Typical year weather file (see Section 3.3) Same as Reference Building model 

Design Day Weather Data See Section 3.3 Same as Reference Building model 

Form (area, shape, floors) Same as taxpayer’s building Same as Reference Building model 

Orientation 

Average results of four simulations rotating 

the building 90 degrees starting with the 

same orientation as the taxpayer’s building 

Same as taxpayer’s building 

Envelope 90.1-2001 minimum requirements Same as taxpayer’s building * 

Interior Lighting 90.1-2001 minimum requirements Same as taxpayer’s building * 

HVAC Systems 90.1-2001 minimum requirements Same as taxpayer’s building * 

SHW Systems 90.1-2001 minimum requirements Same as taxpayer’s building * 

Ventilation Requirements Standard 62-1999 (ASHRAE 1999) Same as taxpayer’s building * 

Receptacle Loads California Nonresidential ACM Approval 

Manual Tables N2-2 and N2-3 Same as Reference Building model 

Process Loads California Nonresidential ACM Approval 

Manual §2.4.1.5 Same as Reference Building model 

Exterior Lighting Excluded from the simulations Excluded from the simulations 

Schedules California Nonresidential ACM Approval 

Manual Tables N2-2 and N2-3 Same as Reference Building model 

Infiltration California Nonresidential ACM Approval 

Manual §2.4.1.6 Same as Reference Building model 

* For a partially qualifying property, the nonqualifying systems in the Proposed Building model must match the 

systems in the Reference Building model. 

3.5 Internal Loads and Schedules 

The internal loads and operating schedules used in the energy simulations shall be the same for the 

Reference Building and the Proposed Building models. Use the internal loads and schedules from the 

California Nonresidential ACM Approval Manual listed in Table 6 and included in Appendix C of this 

document. The occupancy schedules include schedules for occupancy, heating, cooling, fans, lights, 

equipment, infiltration, and hot water. 

Use the operating schedules for the taxpayer’s building if they are known and if they are different from 

the daily schedules in the California Nonresidential ACM Approval Manual. Document the schedules 

used in the simulations. 

Table 6 Internal Loads and Schedules (Included as Appendix C) 

Load/Schedule Source 

Occupancy Rates California Nonresidential ACM Approval Manual Tables N2-2 and N2-3 

Occupant Loads California Nonresidential ACM Approval Manual Tables N2-2 and N2-3 

Hot Water Loads California Nonresidential ACM Approval Manual Tables N2-2 and N2-3 

Receptacle Loads California Nonresidential ACM Approval Manual Tables N2-2 and N2-3 

Process Loads California Nonresidential ACM Approval Manual Section 2.4.1.5 

Occupancy Schedules California Nonresidential ACM Approval Manual Tables N2-4 to N2-9 

 6 
3.6 Use of Standard 90.1-2004 Appendix G 

The PRM in Appendix G of Standard 90.1-2004 provides a method for rating the performance of building 

designs that exceed the requirements of the standard. IRS Notice 2006-52 states that this method shall be 

used to estimate the energy and power cost savings of the taxpayer’s building. Appendix G was 

developed to work with the 2004 version of Standard 90.1; however, EPAct 2005 specifies the use of 

Standard 90.1-2001. Table 7 lists changes to sections in Appendix G in Standard 90.1-2004 to align with 

Standard 90.1-2001. The Reference Building as cited in EPAct 2005 and the IRS Notice 2006-52 is the 

same as the Baseline Building in Standard 90.1-2004, Appendix G. 

Table 7 Changes to Standard 90.1-2004 Appendix G PRM 

Appendix G Section Wording Changes and Corresponding Sections in Standard 90.1-2001 

G1.2 Performance Rating 

The Reference Building model must meet the mandatory provisions of § 5.2, 6.2, 

7.2, 8.2, 9.2, and 10.2 in Standard 90.1-2001. The Proposed Building model 

matches the Reference Building model except for the systems applying for the tax 

deductions, which match the taxpayer’s building. 

G1.2 Performance Rating Energy performance savings include only the energy and power costs from the 

interior lighting, HVAC, and SHW systems (see Section 3.1). 

G1.4 Documentation 

Requirements 

The documentation requirements for the tax deductions are defined in IRS Notice 

2006-52 Section 4. 

G2.2 Simulation Program The simulation program must be on DOE’s list of qualified software (see Section 

3.2). 

G2.3 Climate Data See Section 3.3. 

G2.4 Energy Rates 

On-site renewable electricity production shall not be included in the Reference 

Building or in the Proposed Building models. Site-recovered energy is allowed in 

the models. 

G2.5 Exceptional Calculation 

Methods 

Not allowed per IRS Notice 2006-52 6.01(5)(b)(ii). 

Table G3.1(3) Space Use 

Classification 

Use the building type or space type lighting classifications in accordance with § 

9.3.1.1 or 9.3.1.2 in Standard 90.1-2001. 

Table G3.1(4) Schedules California Nonresidential ACM Approval Manual or the taxpayer’s building if they 

are known (see Section 3.6). 

Table G3.1(5) Building 

Envelope 

Reference Building Performance

The Reference Building shall follow Appendix G with the following changes: 

(b) Opaque Assemblies: Match the thermal properties in Tables B-1 through B-26 

in Standard 90.1-2001. 

(c) Vertical Fenestration: Fenestration U-factors and solar heat gain coefficients 

shall match the values for Ufixed and SHGCall in Tables B-1 through B-26 in 

Standard 90.1-2001. 

(d) Skylights and Glazed Smoke Vents: Skylight U-factors and solar heat gain 

coefficients shall match the values for Ufixed and SHGCall in Tables B-1 through B26 in Standard 90.1-2001. 

(f) Existing Buildings: The Reference Building shall meet the requirements of 

Standard 90.1-2001. 

Proposed Building Performance

For a partially qualifying lighting or HVAC and SHW property, the Proposed 

Building model shall match the Reference Building model. 

For a fully qualifying property or a partially qualifying envelope property, the 

Proposed Building model shall match the taxpayer’s building following Appendix 

G modeling exceptions. 

 7 
Appendix G Section Wording Changes and Corresponding Sections in Standard 90.1-2001 

Table G3.1(6) Lighting 

Reference Building Performance

Determine the allowed lighting power according to § 9.3 in Standard 90.1-2001.

Proposed Building Performance

For a partially qualifying envelope or HVAC and SHW property, the Proposed 

Building model shall match the Reference Building model. 

For a fully qualifying property or a partially qualifying lighting property, the 

Proposed Building model shall match the taxpayer’s building with the following 

changes: 

(b) For lighting systems that have been designed, the lighting power shall be 

determined using luminaire power values from the California Nonresidential ACM 

Approval Manual Appendix NB (CEC 2004 and Appendix D of this document) or 

manufacturer’s data. 

(c) The interior lighting system must be specified. 

(f) Credit may be taken for the use of automatic controls for daylight utilization 

only if their operation is modeled in the energy simulation software. 

Table G3.1(10) HVAC 

Systems 

Reference Building Performance

The Reference Building model shall follow Appendix G guidelines. 

Proposed Building Performance

For a partially qualifying envelope or lighting property, the Proposed Building 

model shall match the Reference Building model. 

For a fully qualifying property or a partially qualifying HVAC and SHW property, 

the Proposed Building model shall match the taxpayer’s building following 

Appendix G modeling rules with the following change: 

 (b) Use the standard rating conditions in § 6.2.1 in Standard 90.1-2001 if 

necessary. 

G3.1.2.1 Equipment 

Efficiencies 

The Reference Building model equipment efficiencies shall match the minimum 

values in § 6.2.1 in Standard 90.1-2001. For a partially qualifying lighting or 

envelope property, the Proposed Building model shall match the Reference 

Building model. For a fully qualifying property or a partially qualifying HVAC and 

SHW property, the Proposed Building model equipment efficiencies shall match 

the taxpayer’s building. 

G3.1.2.6 Economizers 

The Reference Building model economizers shall meet the requirements of § 

6.3.1 in Standard 90.1-2001. For a partially qualifying lighting or envelope 

property, the Proposed Building model shall match the Reference Building model. 

For a fully qualifying property or a partially qualifying HVAC and SHW property, 

the Proposed Building model shall match the taxpayer’s building. 

G3.1.2.9 Supply Fan Power 

The Reference Building model fan power shall be determined based on § 6.3.3.1 

in Standard 90.1-2001. For a partially qualifying lighting or envelope property, the 

Proposed Building model shall match the Reference Building model. For a fully 

qualifying property or a partially qualifying HVAC and SHW property, the 

Proposed Building model shall match the taxpayer’s building. 

G3.1.2.10 Exhaust Air Energy 

Recovery 

The Reference Building model shall meet the requirements of § 6.3.6.1 in 

Standard 90.1-2001. For a partially qualifying lighting or envelope property, the 

Proposed Building model shall match the Reference Building model. For a fully 

qualifying property or a partially qualifying HVAC and SHW property, the 

Proposed Building model shall match the taxpayer’s building. 

G3.1.3.14 and G3.1.3.15 Fan 

Power and Part Load 

Performance 

The Reference Building model shall meet the requirements of § 6.3.3.2.1 in 

Standard 90.1-2001. For a partially qualifying lighting or envelope property, the 

Proposed Building model shall match the Reference Building model. For a fully 

qualifying property or a partially qualifying HVAC and SHW property, the 

Proposed Building model shall match the taxpayer’s building. 

Table G3.1(11) Service Hot 

Water Systems 

The Reference Building model shall follow Appendix G using the minimum 

equipment efficiency requirements of § 7.2.2 and § 6.3.6.2 in Standard 90.1-2001 

for Heat Recovery for Service Water Heating. For a partially qualifying lighting or 

envelope property, the Proposed Building model shall match the Reference 

Building model. For a fully qualifying property or a partially qualifying HVAC and 

SHW property, the Proposed Building model shall match the taxpayer’s building. 

 8 
Appendix G Section Wording Changes and Corresponding Sections in Standard 90.1-2001 

Table G3.1(12) Receptacle 

and Other Loads 

The receptacle and other loads for both building models shall be identical (see 

Section 3.5 of this document). 

Table G3.1(13) Modeling 

Limitations to the Simulation 

Program 

The simulation program must contain calculation methodologies for the building 

components being modeled per IRS Notice 2006-52 6.01(5)(b)(ii). 

3.7 Model Documentation 

The Reference Building and the Proposed Building models shall be documented to show that: 

1. The Reference Building model meets the minimum requirements of Standard 90.1-2001. 

2. The Proposed Building model matches the Reference Building model except for the systems 

qualifying for the tax deduction, which must match the taxpayer’s building. 

The models can be documented by reports generated by the modeling software, by manually completing 

the compliance forms from the Standard 90.1-2001 User’s Manual, or on equivalent forms. The list of 

approved software is available from DOE at www.eere.energy.gov/buildings/info/qualified_software/. 

The Standard 90.1 User’s Manual compliance forms can be downloaded from ASHRAE at 

www.ashrae.org/technology/page/97. Specific guidance for each system is provided below: 

Building Envelope

Document that the Reference Building model meets the Standard 90.1-2001 envelope performance 

requirements. For a partially qualifying lighting or HVAC and SHW property, document that the 

Proposed Building model matches the Reference Building model. For a fully qualifying property or a 

partially qualifying envelope property, document that the Proposed Building model matches the 

taxpayer’s building, which must also meet the mandatory requirements according to the requirements of 

Section 4.1 of Standard 90.1-2001. 

Interior Lighting

1. Document that the lighting power for the Reference Building model meets the allowable lighting 

power per Standard 90.1-2001. 

2. Document that the lighting power for the Proposed Building model matches the Reference Building 

model for partially qualifying envelope or HAVC and SHW properties, or that the lighting power for 

the Proposed Building model matches the taxpayer’s building for partially qualifying lighting or fully 

qualifying properties. 

3. Document the lighting controls specified for the Proposed Building model in Table LF2 in Appendix 

A or with copies of the building plans and specifications. Include a short description of the controls 

and set points for each lighting system. 

HVAC and SHW Systems

1. Document that the HVAC and SHW systems for the Reference Building model meet the minimum 

requirements of Standard 90.1-2001 and match the system type requirements in Standard 90.1-2004 

Appendix G. 

2. Document that the HVAC and SHW systems for the Proposed Building model match the Reference 

Building model for partially qualifying envelope or lighting properties, or that the HVAC and SHW 

systems for the Proposed Building model match the taxpayer’s building for partially qualifying 

 9 
HVAC and SHW or fully qualifying properties, which must also meet the mandatory requirements 

according to the requirements of Section 4.1 of Standard 90.1-2001. 

3. Document systems in the Proposed Building model that are not covered in the Standard 90.1 

mandatory provisions. Include fans and pumps greater than or equal to 5 hp, economizer operation, 

thermal energy storage systems, energy recovery systems, natural ventilation, demand controlled 

ventilation, desiccant systems, combined heat and power systems, and other energy systems 

associated with the HVAC and SHW systems. Include in the documentation the equipment type, 

manufacturer model (if available), size, operating conditions, efficiencies, and control sequences. 

This information can be documented by including copies of the appropriate pages from the building 

plans and specifications. 

4 Inspection Guidelines 

This section provides guidelines for inspection of the systems in the taxpayer’s building. The inspection 

must be completed by a qualified individual as defined in IRS Notice 2006-52 after the building has been 

placed in service. Only the systems being used for the tax deductions need to be inspected. There are two 

objectives for the inspection: 

• Verify that the energy efficient properties qualifying for the tax deductions in the taxpayer’s 

building meet the necessary mandatory provisions of Standard 90.1-2001. 

• Verify that the specifications of the energy systems installed in the taxpayer’s building used for 

the tax deductions meet or exceed the performance of the energy systems used in the Proposed 

Building model. 

The qualified individual shall use the Standard 90.1-2001 compliance forms from the Standard 90.1-2001 

User’s Manual or equivalent forms to document that the necessary mandatory provisions required by 

Section 4.1 of Standard 90.1-2001 have been met in the taxpayer’s building. Make necessary adjustments 

to the forms allowed by Section 4.1.2 of Standard 90.1-2001 for additions or alterations to existing 

buildings. These forms can be downloaded from ASHRAE at www.ashrae.org/technology/page/97. The 

results of the inspection shall be compared with the Proposed Building model documentation to ensure 

that the systems used for tax deductions in the taxpayer’s building meet or exceed the Proposed Building 

model performance specifications. Specific guidance for each system is provided below: 

Building Envelope

For partially qualifying envelope or fully qualifying properties, complete the Standard 90.1-2001 building 

envelope compliance form or equivalent form to ensure that the taxpayer’s building meets or exceeds the 

Standard 90.1-2001 mandatory provisions according to the requirements in Section 4.1 in Standard 90.1-

2001, and meets or exceeds the performance of the Proposed Building model. 

Interior Lighting

For partially qualifying lighting or fully qualifying properties: 

1. Complete the mandatory provision checklist on the Standard 90.1-2001 lighting compliance form or 

equivalent form to ensure that the taxpayer’s building meets or exceeds the Standard 90.1-2001 

mandatory provisions according to the requirements in Section 4.1 in Standard 90.1-2001. 

2. Complete all the connected lighting power tables on the Standard 90.1-2001 lighting compliance form 

or equivalent form and ensure that the total lighting power is less than or equal to the lighting power 

in the Proposed Building model. 

3. Record the IESNA recommended minimum and the measured illuminance for each space in Table 

LF1 or equivalent table for the Taxpayer’s Building. Record the average of measurements taken on 

 10 
the working surfaces or at the locations listed by the IESNA handbook. The average shall equal or 

exceed the IESNA recommended minimum illuminance levels. In addition, no more than 2.5% of the 

measurements should be below 1/3 of the IESNA recommended minimum illuminance levels. This 

latter requirement follows a normal distribution assuming that two standard deviations equals 1/3 of 

the IESNA recommended illuminance level. Measurements only need to be completed once for each 

unique space and lighting arrangement. 

4. Verify that the lighting controls match the performance of the controls specified in the Proposed 

Building energy model in Table LF2 or equivalent documentation. If the controls in the taxpayer’s 

building are different than in the Proposed Building model, the Proposed Building model should be 

changed to match the taxpayer’s building and resimulated to ensure the correct energy and power cost 

savings are achieved. 

HVAC and SHW Systems

For partially qualifying HVAC and SHW or fully qualifying properties: 

1. Fill out the Standard 90.1-2001 compliance form for HVAC and SHW systems or equivalent form to 

ensure that the taxpayer’s building design meets or exceeds the Standard 90.1-2001 mandatory 

provisions and the Proposed Building model according to the requirements in Section 4.1 in Standard 

90.1-2001. 

2. Verify against the documentation completed during the energy modeling of other systems not covered 

in the Standard 90.1 mandatory provisions. This inspection includes fans and pumps greater than or 

equal to 5 hp, economizer operation, thermal energy storage systems, energy recovery systems, 

natural ventilation, demand controlled ventilation, desiccant systems, combined heat and power 

systems, and other energy systems. Include in the inspection the equipment type, manufacturer model 

(if available), size, operating conditions, efficiencies, and control sequences. 

3. Verify that the HVAC and SHW controls match the performance of the controls specified in the 

Proposed Building energy model. If the systems in the taxpayer’s building are less efficient than in 

the Proposed Building model, the Proposed Building model should be changed to match the 

taxpayer’s building and resimulated to ensure the correct energy and power cost savings are achieved. 

5 References 

ASHRAE (1999). ANSI/ASHRAE Standard 92-1999 Ventilation for Acceptable Indoor Air Quality. 

Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. 

ASHRAE (2001). ANSI/ASHRAE/IESNA Standard 90.1-2001 Energy Standard for Buildings Except 

Low-Rise Residential Buildings. Atlanta, GA: American Society of Heating, Refrigerating and AirConditioning Engineers, Inc. 

ASHRAE (2004). ANSI/ASHRAE/IESNA Standard 90.1-2004 Energy Standard for Buildings except 

Low-Rise Residential Buildings. Atlanta, GA: American Society of Heating, Refrigerating and AirConditioning Engineers, Inc. 

ASHRAE (2005). ASHRAE Handbook of Fundamentals. Atlanta, GA: American Society of Heating, 

Refrigerating and Air-Conditioning Engineers, Inc. 

 11 
ASHRAE (2006). ASHRAE Standard 169-2006 Weather Data for Building Design Standards. Atlanta, 

GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. 

CEC (2004). Nonresidential Alternative Calculation Method (ACM) Approval Manual. P400-03-004F. 

Sacramento, CA: California Energy Commission. www.energy.ca.gov/title24/index.html 

 12 
Appendix A – Lighting System Compliance Form 

Project Name: Date: 

Project Address: 

Building Owner (name and address of all taxpayers claiming a tax 

deduction): 

Telephone: 

Energy Modeler (name and address): Telephone: 

Energy Inspector (name and address): Telephone: 

Table LF1 Illuminance Levels 

Building / Space 

IESNA 2000 

Minimum 

(lux) 

Taxpayer’s 

Building 

Measured 

(lux) 

Lighting Compliance Form 13 
Table LF2 Lighting Controls Description in the Proposed Building Energy Model 

Building / Space Proposed Building Model 

Control System and Set Points 

Table LF3 Lighting Controls Description in the Taxpayer’s Building 

Building / Space Taxpayer’s Building 

Control System and Set Points 

Table LF4 Additional Lighting Systems Mandatory Provisions Checklist for the Interim Lighting 

Rule 

Provision Taxpayer’s 

Building 

Include provision for bi-level switching in all occupancies 

Exception: hotel and motel guest rooms, store rooms, restrooms, and public 

lobbies 

Lighting Compliance Form 14 
Appendix B – 2005 California Nonresidential ACM Approval Manual 

Infiltration Modeling Rules 

2.4.1.6 Infiltration 

Modeling Rules for 

Proposed Design: 

Infiltration shall be modeled as either "ON" or "OFF" for each zone, according to 

the following: 

• "OFF" if fans are ON and zone supply air quantity (including transfer air) is 

greater than zone exhaust air quantity. 

• "ON" if fans are OFF. 

When infiltration is "ON," the reference method calculates the infiltration rate as 

0.038 cfm per square foot of gross exterior partition (walls and windows) area for 

the zone. 

Modeling Rules for 

Standard Design (All): 

ACMs shall model infiltration for the standard design exactly the same as the 

proposed design. 

15 
Appendix C – 2005 California Nonresidential ACM Approval Manual 

Internal Loads and Schedules 

Table N2-2 Occupancy Assumptions When Lighting Plans Are Submitted for the Entire 

Building or When Lighting Compliance Is not Performed 

Occupancy Type 

# People 

per 1000 

ft2 (1) 

Sensible 

Heat per 

Person (2)

Latent 

Heat per 

Person (2)

Receptacle 

Load W/ft2 

(3) 

Hot Water 

Btu/h per 

Person 

Lighting 

W/ft2 (4) 

Ventilation 

CFM/ft2 (5) 

Auditoriums (8) 143 245 105 1.0 60 1.5 1.07 

Convention Centers (8) 136 245 112 0.96 57 1.3 1.02 

Financial Institutions 10 250 250 1.5 120 1.1 0.15 

General Commercial 

and Industrial Work 

Buildings, High Bay 7 375 625 1.0 120 1.1 0.15 

General Commercial 

and Industrial Work 

Buildings, Low Bay 7 375 625 1.0 120 1.0 0.15 

Grocery Stores (8) 29 252 225 0.91 113 1.5 0.22 

Hotel (6) 20 250 200 0.5 60 1.4 0.15 

Industrial and 

Commercial Storage 

Buildings 5 268 403 0.43 108 0.7 0.15 

Medical Buildings and 

Clinics 10 250 213 1.18 110 1.1 0.15 

Office Buildings 10 250 206 1.34 106 1.1 0.15 

Religious Facilities (8) 136 245 112 0.96 57 1.6 1.03 

Restaurants (8) 45 274 334 0.79 366 1.2 0.38 

Retail and Wholesale 

Stores (8) 29 252 224 0.94 116 1.5 0.22 

Schools (8) 40 246 171 1.0 108 1.2 0.32 

Theaters (8) 130 268 403 0.54 60 1.3 0.98 

All Others 10 250 200 1.0 120 0.6 0.15 

(1) Most occupancy values are based on an assumed mix of sub-occupancies within the area. These values were based on onehalf the maximum occupant load for exiting purposes in the CBC. Full value for design conditions. Full year operational 

schedules reduce these values by up to 50% for compliance simulations and full year test simulations. 

(2) From Table 1, p. 29.4, ASHRAE 2001Handbook of Fundamentals 

(3) From Lawrence Berkeley Laboratory study. This value is fixed and includes all equipment plugged into receptacle outlets. 

(4) From Table 146-B of the Standards for the applicable occupancy. The LPD of the standard building, for areas where no 

lighting plans or specifications are submitted for permit and the occupancy of the building is not known, is 1.2 W.ft2

. 

(5) Developed from Section 121 and Table 121-A of the Standards 

(6) Hotel uses values for Hotel Function Area from Table N2-3. 

(7) For retail and wholesale stores, the complete building method may only be used when the sales area is 70% or greater of the 

building area. 

(8) For these occupancies, when the proposed design is required to have demand control ventilation by Section 121 ( c) 3 the 

ventilation rate is the minimum that would occur at any time during occupied hours. Additional ventilation would be 

provided through demand controlled ventilation to maintain CO2 levels according to Section 121 of the Standards. 

16 
Table N2-3 Area Occupancy Assumptions When Lighting Plans are Submitted for 

Portions or for the Entire Building or When Lighting Compliance is not Performed 

Sub-Occupancy Type (1) People 

per 1000

ft2

 (2) 

Sensible

Heat per

Person 

(3)

Latent 

Heat per

Person

(3) 

Recept 

acle 

Load 

W/ft2 (4) 

Hot 

Water 

Btu/h per

Person 

Lighting 

W/ft2 (5) 

Ventilation

CFM/ft2

(6) 

Auditorium (10) 143 245 105 1.0 60 1.5 1.07 

Auto Repair 10 275 475 1.0 120 1.1 1.50 

Bar, Cocktail Lounge and Casino (10) 67 275 275 1.0 120 1.1 0.50 

Barber and Beauty Shop 10 250 200 2.0 120 1.0 0.40 

Classrooms, Lecture, Training, Vocational Room 50 245 155 1.0 120 1.2 0.38 

Civic Meeting Space (10) 25 250 200 1.5 120 1.3 0.19 

Commercial and Industrial Storage 3 275 475 0.2 120 0.6 0.15 

Convention, Conference, Multi-purpose and 

Meeting Centers (10) 

67 245 155 1.0 60 1.4 0.50 

Corridors, Restrooms, Stairs, and Support Areas 10 250 250 0.2 0 0.6 0.15 

Dining (10) 67 275 275 0.5 385 1.1 0.50 

Electrical, Mechanical Room 3 250 250 0.2 0 0.7 0.15 

Exercise, Center, Gymnasium 20 255 875 0.5 120 1.0 0.15 

Exhibit, Museum (10) 67 250 250 1.5 60 2.0 0.50 

Financial Transaction 10 250 250 1.5 120 1.2 0.15 

Dry Cleaning (Coin Operated) 10 250 250 3.0 120 0.9 0.30 

Dry Cleaning (Full Service Commercial) 10 250 250 3.0 120 0.9 0.45 

General Commercial and Industrial Work, High Bay 10 275 475 1.0 120 1.1 0.15 

General Commercial and Industrial Work, Low Bay 10 275 475 1.0 120 1.0 0.15 

General Commercial and Industrial Work, Precision 10 250 200 1.0 120 1. 3 0.15 

Grocery Sales (10) 33 250 200 1.0 120 1.6 0.25 

High-Rise Residential Living Spaces (9) 5 245 155 0.5 (7) 0.5 0.15 

Hotel Function Area (10) 67 250 200 0.5 60 1.5 0.50 

Hotel/Motel Guest Room (9) 5 245 155 0.5 2800 0.5 0.15 

Housing, Public and Common Areas, Multi-family 10 250 250 0.5 120 1.0 0.15 

Housing, Public and Common Areas, Dormitory, 

Senior Housing 

10 250 250 0.5 120 1.5 0.15 

Kitchen, Food Preparation 5 275 475 1.5 385 1.6 0.15 

Laundry 10 250 250 3.0 385 0.9 0.15 

Library, Reading Areas 20 250 200 1.5 120 1.2 0.15 

Library, Stacks 10 250 200 1.5 120 1.5 0.15 

Lobby, Hotel 10 250 250 0.5 120 1.1 0.15 

Lobby, Main Entry 10 250 250 0.5 60 1.5 0.15 

Locker/Dressing Room 20 255 475 0.5 385 0.8 0.15 

Lounge, Recreation (10) 67 275 275 1.0 60 1.1 0.50 

Malls and Atria (10) 33 250 250 0.5 120 1.2 0.25 

Medical and Clinical Care 10 250 200 1.5 160 1.2 0.15 

Office 10 250 200 1.5 120 1.2 0.15 

Police Station and Fire Station 10 250 200 1.5 120 0.9 0.15 

Religious Worship (10) 143 245 105 0.5 60 1.5 1.07 

17 
Sub-Occupancy Type (1) People 

per 1000

ft2

 (2) 

Sensible

Heat per

Person 

(3)

Latent 

Heat per

Person

(3) 

Recept 

acle 

Load 

W/ft2 (4) 

Hot 

Water 

Btu/h per

Person 

Lighting 

W/ft2 (5) 

Ventilation

CFM/ft2

(6) 

Retail Merchandise Sales, Wholesale 

Showroom (10) 33 250 200 1.0 120 1.7 0.25 

Tenant Lease Space 10 250 200 1.5 120 1.0 0.15 

Theater, Motion Picture (10) 143 245 105 0.5 60 0.9 1.07 

Theater, Performance (10) 143 245 105 0.5 60 1.4 1.07 

Transportation Function (10) 33 250 250 0.5 120 1.2 0.25 

Waiting Area 10 250 250 0.5 120 1.1 0.15 

All Other 10 250 200 1.0 120 0.6 0.15 

(1) Subcategories of these suboccupancies are described in Section 2.4.1.1 (Occupancy Types) of this manual. 

(2) Values based on one-half the maximum occupant load for exiting purposes in the CBC. Full value for design conditions. 

Full year operational schedules reduce these values by up to 50% for compliance simulations and full year test simulations. 

(3) From Table 1, p. 29.4, ASHRAE 2001 Handbook of Fundamentals. 

(4) From Lawrence Berkeley Laboratory study. This value is fixed and includes all equipment that is plugged into receptacle 

outlets. 

(5) From Table 146-C of the Standards for the applicable occupancy. ACMs shall use this value for the standard building design 

when lighting compliance is performed for the zone or area in question. 

(6) Developed from Section 121 and Table 121-A of the Standards. 

(7) Refer to residential water heating method. 

(8) The use of this occupancy category is an exceptional condition that shall appear on the exceptional conditions checklist and 

thus requires special justification and documentation and independent verification by the local enforcement agency. 

(9) For hotel/motel guest rooms and high-rise residential living spaces all these values are fixed and are the same for both the 

proposed design and the standard design. ACMs shall ignore user inputs that modify these assumptions for these two 

occupancies. Spaces in high-rise residential buildings other than living spaces, shall use the values for Housing, Public and 

Common Areas (either multi-family or senior housing). 

(10) For these occupancies, when the proposed design is required to have demand control ventilation by Section 121 ( c) 3 the 

ventilation rate is the minimum that would occur at any time during occupied hours. Additional ventilation would be 

provided through demand controlled ventilation to maintain CO2 levels according to Section 121 of the Standards. 

18 
Table N2-4 Schedule Types of Occupancies and Sub-Occupancies 

Occupancy or Sub-Occupancy Type Schedule 

Atrium Table 2-5 Nonresidential 

Auditorium Table 2-5 Nonresidential 

Auto Repair Table 2-5 Nonresidential 

Bar, Cocktail Lounge and Casino Table 2-5 Nonresidential 

Barber and Beauty Shop Table 2-5 Nonresidential 

Classrooms, Lecture, Training, Vocational Room Table 2-5 Nonresidential 

Civic Meeting Space Table 2-5 Nonresidential 

Commercial and Industrial Storage Table 2-5 Nonresidential 

Convention, Conference, Multipurpose, and Meeting Centers Table 2-5 Nonresidential 

Corridors, Restrooms, Stairs, and Support Areas Table 2-5 Nonresidential 

Dining Table 2-5 Nonresidential 

Electrical, Mechanical Room Table 2-5 Nonresidential 

Exercise Center, Gymnasium Table 2-5 Nonresidential 

Exhibit, Museum Table 2-5 Nonresidential 

Financial Transaction Table 2-5 Nonresidential 

Dry Cleaning (Coin Operated) Table 2-5 Nonresidential 

Dry Cleaning (Full Service Commercial) Table 2-5 Nonresidential 

General Commercial and Industrial Work, High Bay Table 2-5 Nonresidential 

General Commercial and Industrial Work, Low Bay Table 2-5 Nonresidential 

General Commercial and Industrial Work, Precision Table 2-5 Nonresidential 

Grocery Sales Table 2-5 Nonresidential 

High-rise Residential with Setback Thermostat Table 2-7 Residential / with Setback 

High-rise Residential without Setback Thermostat Table 2-8 Residential / without Setback 

Hotel Function Area Table 2-6 Hotel Function 

Hotel/Motel Guest Room with Setback Thermostat Table 2-7 Residential / with Setback 

Hotel/Motel Guest Room without Setback Thermostat Table 2-8 Residential / without Setback 

Housing, Public and Commons Areas, Multi-family with Setback 

Thermostat Table 2-7 Residential / with Setback 

Housing, Public and Commons Areas, Multi-family without Setback 

Table 2-8 Residential / without Setback 

Thermostat 

Housing, Public and Common Areas, Dormitory, Senior Housing with 

Setback 

Table 2-7 Residential / with Setback 

Thermostat 

Housing, Public and Commons Areas, Dormitory, Senior Housing 

without 

Table 2-8 Residential / without Setback 

Setback Thermostat 

Kitchen, Food Preparation Table 2-5 Nonresidential 

Laundry Table 2-5 Nonresidential 

Library, Reading Areas Table 2-5 Nonresidential 

Library, Stacks Table 2-5 Nonresidential 

Lobby, Hotel Table 2-6 Hotel Function 

Lobby, Main Entry Table 2-5 Nonresidential 

Locker/Dressing Room Table 2-5 Nonresidential 

Lounge, Recreation Table 2-5 Nonresidential 

Mall Table 2-9 Retail 

Medical and Clinical Care Table 2-5 Nonresidential 

Office Table 2-5 Nonresidential 

Police Station and Fire Station Table 2-5 Nonresidential 

19 
Occupancy or Sub-Occupancy Type Schedule 

Religious Worship Table 2-5 Nonresidential 

Retail Merchandise Sales, Wholesale Showroom Table 2-9 Retail 

Tenant Lease Space Table 2-5 Nonresidential 

Theater, Motion Picture Table 2-5 Nonresidential 

Theater, Performance Table 2-5 Nonresidential 

Transportation Function Table 2-5 Nonresidential 

Waiting Area Table 2-5 Nonresidential 

All Other Table 2-5 Nonresidential 

20 
Table N2-5 Nonresidential Occupancy Schedules (Other than Retail) 

Hour 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 

Heating WD 60 60 60 60 60 65 65 70 70 70 70 70 70 70 70 70 70 70 65 60 60 60 60 60 

(oF) Sat 60 60 60 60 60 65 65 65 65 65 65 65 65 65 65 65 60 60 60 60 60 60 60 60 

Sun 60 60 60 60 60 65 65 65 65 65 65 65 65 65 65 65 60 60 60 60 60 60 60 60 

Cooling WD 77 77 77 77 77 73 73 73 73 73 73 73 73 73 73 73 73 73 77 77 77 77 77 77 

(oF) Sat 77 77 77 77 77 73 73 73 73 73 73 73 73 73 73 73 73 73 77 77 77 77 77 77 

Sun 77 77 77 77 77 73 73 73 73 73 73 73 73 73 73 73 73 73 77 77 77 77 77 77 

Lights WD 5 5 5 5 10 20 40 70 80 85 85 85 85 85 85 85 85 80 35 10 10 10 10 10 

(%) Sat 5 5 5 5 5 10 15 25 25 25 25 25 25 25 20 20 20 15 10 10 10 10 10 10 

Sun 5 5 5 5 5 10 10 15 15 15 15 15 15 15 15 15 15 10 10 10 5 5 5 5 

Equipment WD 15 15 15 15 15 20 35 60 70 70 70 70 70 70 70 70 65 45 30 20 20 15 15 15 

(%) Sat 15 15 15 15 15 15 15 20 25 25 25 25 25 25 20 20 20 15 15 15 15 15 15 15 

Sun 15 15 15 15 15 15 15 20 20 20 20 20 20 20 20 20 20 15 15 15 15 15 15 15 

Fans WD off off off off off on on on on on on on on on on on on on on on off off off off 

Sat off off off off on on on on on on on on on on on off off off off off off off off off 

Sun off off off off off off off off off off off off off off off off off off off off off off off off 

Infiltration WD 100 100 100 100 100 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 100 100 100 100

(%) Sat 100 100 100 100 100 0 0 0 0 0 0 0 0 0 0 100 100 100 100 100 100 100 100 100

Sun 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100

People WD 0 0 0 0 5 10 25 65 65 65 65 60 60 65 65 65 65 40 25 10 5 5 5 0 

(%) Sat 0 0 0 0 0 0 5 15 15 15 15 15 15 15 15 15 15 5 5 5 0 0 0 0 

Sun 0 0 0 0 0 0 0 5 5 5 5 5 5 5 5 5 5 5 5 5 0 0 0 0 

Hot Water WD 0 0 0 0 10 10 50 50 50 50 70 90 90 50 50 70 50 50 50 10 10 10 10 0 

(%) Sat 0 0 0 0 0 0 10 20 20 20 20 20 20 20 20 20 20 10 10 10 0 0 0 0 

Sun 0 0 0 0 0 0 0 10 10 10 10 10 10 10 10 10 10 10 10 10 0 0 0 0 

21 
Table N2-6 Hotel Function Occupancy Schedules 

Hour 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 

Heating WD 55 55 55 55 55 55 63 68 70 70 70 70 70 70 70 70 70 70 70 70 70 70 55 55 

(oF) Sat 55 55 55 55 55 55 63 68 70 70 70 70 70 70 70 70 70 70 70 70 70 70 55 55 

Sun 55 55 55 55 55 55 63 68 70 70 70 70 70 70 70 70 70 70 70 70 70 70 55 55 

Cooling WD 95 95 95 95 95 95 95 95 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 95 

(oF) Sat 95 95 95 95 95 95 95 95 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 95 

Sun 95 95 95 95 95 95 95 95 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 95 

Lights WD 5 5 5 5 5 5 5 5 25 50 90 90 90 90 90 90 75 50 50 50 50 10 5 5 

(%) Sat 5 5 5 5 5 5 5 5 25 50 90 90 90 90 90 90 75 50 50 50 50 10 5 5 

Sun 5 5 5 5 5 5 5 5 25 50 90 90 90 90 90 90 75 50 50 50 50 10 5 5 

Equipment WD 5 5 5 5 5 5 5 5 50 50 50 50 30 50 50 50 30 10 30 30 30 10 5 5 

(%) Sat 5 5 5 5 5 5 5 5 50 50 50 50 30 50 50 50 30 10 30 30 30 10 5 5 

Sun 5 5 5 5 5 5 5 5 50 50 50 50 30 50 50 50 30 10 30 30 30 10 5 5 

Fans WD off off off off off off on on on on on on on on on on on on on on on on on off 

Sat off off off off off off on on on on on on on on on on on on on on on on on off 

Sun off off off off off off on on on on on on on on on on on on on on on on on off 

Infiltration WD 100 100 100 100 100 100 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 100

(%) Sat 100 100 100 100 100 100 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 100

Sun 100 100 100 100 100 100 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 100

People WD 0 0 0 0 0 0 0 5 35 90 90 90 25 90 90 90 50 25 50 50 50 10 0 0 

(%) Sat 0 0 0 0 0 0 0 5 35 90 90 90 25 90 90 90 50 25 50 50 50 10 0 0 

Sun 0 0 0 0 0 0 0 5 35 90 90 90 25 90 90 90 50 25 50 50 50 10 0 0 

Hot Water WD 0 0 0 0 0 0 0 5 35 90 90 90 25 90 90 90 50 25 50 50 50 10 0 0 

(%) Sat 0 0 0 0 0 0 0 5 35 90 90 90 25 90 90 90 50 25 50 50 50 10 0 0 

Sun 0 0 0 0 0 0 0 5 35 90 90 90 25 90 90 90 50 25 50 50 50 10 0 0 

22 
Table N2-7 Residential Occupancy Schedules (Including Hotel/Motel Guest Rooms) with 

Setback Thermostat for Heating 

Hour 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 

Heating WD 60 60 60 60 60 60 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 60 60 

(oF) Sat 60 60 60 60 60 60 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 60 60 

Sun 60 60 60 60 60 60 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 60 60 

Cooling WD 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 

(oF) Sat 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 

Sun 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 

Lights WD 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

(%) Sat 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

Sun 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

Equipment WD 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

(%) Sat 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

Sun 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

Fans WD on on on on on on on on on on on on on on on on on on on on on on on on 

Sat on on on on on on on on on on on on on on on on on on on on on on on on 

Sun on on on on on on on on on on on on on on on on on on on on on on on on 

Infiltration WD 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100

(%) Sat 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100

Sun 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100

People WD 90 90 90 90 90 90 70 40 40 20 20 20 20 20 20 30 50 50 50 70 70 80 90 90 

(%) Sat 90 90 90 90 90 90 70 40 40 20 20 20 20 20 20 30 50 50 50 70 70 80 90 90 

Sun 90 90 90 90 90 90 70 40 40 20 20 20 20 20 20 30 50 50 50 70 70 80 90 90 

Hot Water WD 0 0 0 5 5 5 80 70 50 40 25 25 25 25 50 60 70 70 40 25 20 20 5 5 

(%) Sat 0 0 0 5 5 5 80 70 50 40 25 25 25 25 50 60 70 70 40 25 20 20 5 5 

Sun 0 0 0 5 5 5 80 70 50 40 25 25 25 25 50 60 70 70 40 25 20 20 5 5 

23 
Table N2-8 Residential Occupancy Schedules (Including Hotel/Motel Guest Rooms) 

without Setback Thermostat 

Hour 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 

Heating WD 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 

(oF) Sat 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 

Sun 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 

Cooling WD 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 

(oF) Sat 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 

Sun 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 

Lights WD 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

(%) Sat 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

Sun 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

Equipment WD 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

(%) Sat 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

Sun 10 10 10 10 10 30 45 45 45 45 30 30 30 30 30 30 30 30 60 80 90 80 60 30 

Fans WD on on on on on on on on on on on on on on on on on on on on on on on on 

Sat on on on on on on on on on on on on on on on on on on on on on on on on 

Sun on on on on on on on on on on on on on on on on on on on on on on on on 

Infiltration WD 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100

(%) Sat 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100

Sun 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100

People WD 90 90 90 90 90 90 70 40 40 20 20 20 20 20 20 30 50 50 50 70 70 80 90 90 

(%) Sat 90 90 90 90 90 90 70 40 40 20 20 20 20 20 20 30 50 50 50 70 70 80 90 90 

Sun 90 90 90 90 90 90 70 40 40 20 20 20 20 20 20 30 50 50 50 70 70 80 90 90 

Hot Water WD 0 0 0 5 5 5 80 70 50 40 25 25 25 25 50 60 70 70 40 25 20 20 5 5 

(%) Sat 0 0 0 5 5 5 80 70 50 40 25 25 25 25 50 60 70 70 40 25 20 20 5 5 

Sun 0 0 0 5 5 5 80 70 50 40 25 25 25 25 50 60 70 70 40 25 20 20 5 5 

24 
Table N2-9 Retail Occupancy Schedules 

Hour 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 

Heating WD 60 60 60 60 60 63 65 68 70 70 70 70 70 70 70 70 70 70 70 65 65 65 65 60 

(oF) Sat 60 60 60 60 60 63 65 68 70 70 70 70 70 70 70 70 70 70 70 65 65 65 65 60 

Sun 60 60 60 60 60 63 65 68 70 70 70 70 70 70 70 70 70 70 70 65 65 65 65 60 

Cooling WD 80 80 80 80 80 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 80 80 

(oF) Sat 80 80 80 80 80 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 80 80 

Sun 80 80 80 80 80 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 74 80 80 

Lights WD 20 20 20 20 20 30 40 65 90 90 90 90 90 90 90 90 90 90 90 80 65 50 35 25 

(%) Sat 20 20 20 20 20 30 40 65 90 90 90 90 90 90 90 90 90 90 90 80 65 50 35 25 

Sun 20 20 20 20 20 30 40 65 90 90 90 90 90 90 90 90 90 90 90 80 65 50 35 25 

Equipment WD 20 20 20 20 20 25 30 45 60 75 75 75 70 75 75 75 75 75 65 55 45 35 25 20 

(%) Sat 20 20 20 20 20 25 30 45 60 75 75 75 70 75 75 75 75 75 65 55 45 35 25 20 

Sun 20 20 20 20 20 25 30 45 60 75 75 75 70 75 75 75 75 75 65 55 45 35 25 20 

Fans WD off off off off off on on on on on on on on on on on on on on on on off off off 

Sat off off off off off on on on on on on on on on on on on on on on on off off off 

Sun off off off off off on on on on on on on on on on on on on on on on off off off 

Infiltration WD 100 100 100 100 100 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 100 100 100

(%) Sat 100 100 100 100 100 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 100 100 100

Sun 100 100 100 100 100 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 100 100 100

People WD 5 5 5 5 5 5 15 25 40 55 75 75 75 75 75 75 75 75 65 50 35 20 10 5 

(%) Sat 5 5 5 5 5 5 15 25 40 55 75 75 75 75 75 75 75 75 65 50 35 20 10 5 

Sun 5 5 5 5 5 5 15 25 40 55 75 75 75 75 75 75 75 75 65 50 35 20 10 5 

Hot Water WD 0 0 0 0 0 0 10 10 50 50 70 90 90 50 50 70 50 50 50 10 10 0 0 0 

(%) Sat 0 0 0 0 0 0 10 10 50 50 70 90 90 50 50 70 50 50 50 10 10 0 0 0 

Sun 0 0 0 0 0 0 10 10 50 50 70 90 90 50 50 70 50 50 50 10 10 0 0 0 

25 
Appendix D – 2005 California Nonresidential ACM Approval Manual 

Illuminance Categories and Luminaire Power 

26 
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F1147-E(12/2004) 

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4. TITLE AND SUBTITLE

Energy Savings Modeling and Inspection Guidelines for Commercial 

Building Federal Tax Deductions, Second Edition 

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This document provides guidance for modeling and inspecting energy-efficient property in commercial buildings for 

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