U.S. Department of Energy

Energy Efficiency and Renewable Energy

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Building Technologies Program

T OF ENERGY

DEPARTMEN

U

E

NITED STAT S OFA ERICA

M

Duct systems used in forced-air space-conditioning systems are a 

vital element in home energy efficiency. How well a system works 

makes a big difference in the cost and the effectiveness of heating and cooling a home. At the same time, a duct system that 

is poorly designed or maintained can have a detrimental effect 

on the health of the people who live in the house, through the 

unintended distribution of indoor air pollution.

This brochure is intended to provide you with a working knowledge 

of residential heating and cooling duct systems. This includes an 

understanding of the major issues concerning efficiency, comfort, 

health and safety, as well as practical tips on installation and repair 

of duct systems. If you are a contractor, system designer, or 

heating/cooling professional, this information can help make your 

customers’ lives more comfortable, safe, and energy efficient.1

If you are a homeowner, it will allow you to work with a professional to upgrade the efficiency of your home’s heating and 

cooling system. 

Energy Losses and Their Costs

The purpose of a space-conditioning duct system is to convey 

heated or cooled air from the central furnace, heat pump, or air 

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1

The information in this brochure is condensed from a more detailed manual entitled 

Better Duct Systems for Home Heating and Cooling. A shorter consumer-oriented 

guide, Improving the Efficiency of Your Duct System, is also available. Both can be 

accessed at www.eere.energy.gov/buildings/info/publications.html.

Better Duct Systems for Home Heating and Cooling

conditioner to the rooms where it is needed. Typical systems with 

ducts in attics or crawl spaces lose from 25% to 40% of the heating or cooling energy that passes through them. In an era of 

increasing concern for energy efficiency, this is no longer 

acceptable.

Duct systems lose energy in two main ways: by air leakage 

through small cracks and seams and by conduction of heat 

through the duct wall. In addition, how the various systems and 

equipment interact has an effect on how well the ducts perform.

Air Leakage

Ducts lose energy when air leaks into or out of them. Sometimes 

this leakage is from holes in the ducts or from poorly connected 

duct joints. Even if the ducts are sealed, their operation can cause 

the house itself to leak more air because of differences in air 

pressure in various zones of the house. 

Heat Conduction

Duct systems also lose energy when the warm or cool air they 

contain heats or cools the duct walls, which in turn heats or cools 

the air outside the ducts. In winter, ducts that are in an attic or 

vented crawl space that is nearly as cold as the outdoors lose 

this heat completely through the duct wall. If the ducts are in a 

basement, some of this lost heat may be recaptured as it warms 

the basement ceiling enough to reduce heat loss from the house. 

In summer, ducts gain heat from warm surrounding spaces, 

detracting from the air conditioner’s ability to cool the house.

Energy Savings

How much can you save by fixing a duct system or by installing it 

correctly in the first place? Let’s consider two benchmark cases, 

one in a cold climate (Chicago, Illinois) and the other in a hot, 

humid climate (Orlando, Florida). We’ll suppose that in each case 

the ducts are in a location typical of the region—a crawl space 

in Chicago, the attic in Florida—and that their size and insulation 

Acorn Structures/PIX00139
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level are also typical. Furthermore, we’ll assume that they leak 

about as much as an average duct system.2

With these parameters, ASHRAE Standard 1523 can be used to 

calculate an expected average efficiency4 of the duct system 

over an entire heating or cooling season. The results are as 

follows:

• Chicago house: 63% for heating, 83% for cooling

• Orlando house: 74% for heating, 65% for cooling.

Even within a given climate region, different homes and lifestyles 

will have different ratios of heating to cooling. However, as a 

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2

This assumes that the ducts are insulated to R-4 and have 15% leakage on each side 

(supply and return). This leakage level may sound high, but it is a couple of percent less 

than what was found in a recent national laboratory study.

3

ASHRAE Standard 152 is a nationally standardized method for measuring duct efficiency, 

developed by the American Society of Heating, Refrigerating and Air-Conditioning 

Engineers, Inc.

4

Duct efficiency (more precisely, “thermal distribution efficiency”) is calculated as the ratio 

of (a) the fuel energy that would be needed by the system if it had perfect, loss-free ducts 

to (b) the fuel energy needed by the actual system with the as-found ducts. This definition 

accounts for system interactions.

benchmark, let us assume that in Chicago three-quarters of the 

energy requirement of the house is for heating, whereas in 

Orlando three-quarters is for cooling. The average duct efficiency 

will then be 67% in either location. In these typical cases, then, 

one-third of the energy given to the ducts is lost before it gets 

to the living space.

How much better can we do? A reasonable target for a duct 

retrofit would be to reduce the leakage by two-thirds—to 5% 

of the system fan flow on each side of the duct system—and 

increase the insulation level to R-8. This would result in the 

following duct efficiency levels:

• Chicago house: 81% for heating, 90% for cooling

• Orlando house: 86% for heating, 82% for cooling.

Using the same assumptions as above, this results in an average 

duct efficiency of 83% in either location.

With the original ducts, the equipment must provide 150 units of 

comfort in order to deliver 100 units of heating or cooling comfort 

to the house, because only two-thirds (67%) of that comfort makes 

2

A common type of home duct system, showing energy flows and losses.
• original duct leakage less than the benchmark

• leakage predominantly in the return ducts

• original ducts insulated more than R-4.

System Interactions

Duct energy losses and equipment inefficiencies can work 

together to give surprisingly low overall system efficiency. 

When a furnace meeting the current national standards (78% 

Annual Fuel Utilization Efficiency) is combined with a typical duct 

system installed in a vented attic or open crawlspace (60%–75% 

seasonal efficiency), only about half the heating value of the fuel 

will make it into the house!

Heat pumps and air conditioners display the same general trend 

as furnaces, although the calculation is somewhat more involved. 

Two or more energy losses, each of which might seem “not too 

bad” in itself, can add up to a very disappointing result. Ducts are 

too often “out of sight, out of mind.” The combined inefficiency 

of equipment and ducts is the prominent system interaction, but 

more subtle interactions can either lessen its impact or make it 

worse.

Thermal Regain — In most houses in the United States, duct 

systems are located in a space that is not heated or cooled. If this 

unconditioned space is not vented, then heat lost from the ducts 

may warm that space significantly. This increase in temperature 

retards heat loss from the adjacent conditioned living space. 

Heating of the zone also retards further heat conduction through 

it to the living space. With the repaired ducts, the equipment only 

needs to provide 120 units of comfort heating or cooling to get 

100 units (83% of 120) into the house. Thus, the load on the 

equipment is reduced by 30 units, which is 20% of the original 

requirement. The cost of running the equipment also will be 

reduced by 20% over a heating or cooling season.

In new construction, ducts can be placed within the conditioned 

space. If done in a manner that leaves no hidden leakage paths 

to the outside, duct efficiency of 100% is possible. In this case, 

all the heating or cooling provided by the equipment would get 

to the living space, so the energy and cost savings compared 

with a “business as usual” system would be 50 units out of the 

original 150, or 33%. 

These examples are, of course, only benchmarks. Your results 

may vary. The following are some factors that can increase or 

decrease the savings.

Percent savings may be greater for

• more severe climates (e.g., Minneapolis or Miami)

• original duct system leakage greater than the benchmark

• leakage predominantly in the supply ducts 

• original ducts uninsulated or insulated less than R-4.

Percent savings may be less for

• more moderate climates (e.g., Washington, D.C.)

• ducts located in a basement or similar protected zone

3

When placed in a home’s conditioned space, ducts can easily blend into the décor.

Heat losses from the furnace and the ducts can easily add up to half the energy value of 

the fuel that is consumed for heating.

Warren Gretz/PIX03072
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the duct walls themselves. These benefits can soften the energy 

penalty of the losses because some of the lost heat is, in effect, 

recovered. This is called thermal regain.

Locations with the highest thermal regain are the best places to 

install ducts. When located within the conditioned space, ducts 

have 100% regain because the lost heat is used. Unvented, uninsulated basements and crawl spaces have intermediate merit 

as locations for ducts, because about half the heating or cooling 

value of thermal loss is regained. Other duct locations, such as 

vented crawl spaces, attics, and exterior walls have regain factors 

ranging from 30% down to essentially zero and should be avoided 

if possible. 

Equipment Efficiency — Some types of equipment, such as heat 

pumps and variable-capacity air conditioners, might suffer a loss 

of efficiency because of a poorly performing duct system, and this 

penalty is added to the energy losses in the duct system. Installing 

a variable-capacity furnace in a poorly insulated duct system can 

cause an already mediocre duct efficiency to drop off even further. 

Because the furnace is running at low capacity, heated air spends 

more time in the ducts and can, therefore, cool down more before 

it is delivered to the living space. The lesson here is that if you are 

going to use premium equipment, you should also have premium 

ducts.

Pressure Effects — When in operation, the central air-handler 

fan often changes the distribution of pressures within the house.

Thus, for example, a bedroom could have pressure higher than 

the living room. These pressure changes may affect the rate at 

which outdoor air infiltrates into the home, usually increasing the 

heating or cooling load. 

Health, Safety, and Comfort Issues in Residential 

Ducts

Pressure changes caused by the air-handler fan can affect the 

health of the home’s occupants through the unintended distribution of indoor air pollution. Room pressures can also be influenced by the various exhaust fans in the house (bathroom fans, 

vented range hoods, clothes dryers). Therefore, be sure to consider the combined operation of all air movers in the house when 

assessing the potential for health and safety problems.

Safety, health, and comfort can be detrimentally affected by duct leakage.

4
The most common health problems associated with ducts arise 

from the induction of harmful gases, vapors, or particulates into 

the living space in concentrations that are unhealthy, but not 

immediately life-threatening. These contaminants can include 

flue gases from furnaces and water heaters, fumes from stored 

chemicals, and radon (a radioactive gas that comes from the 

ground). 

Potentially lethal concentrations of carbon monoxide gas may be 

pulled into the living space from combustion appliances or 

exhaust from a car left running in the garage. Severe depressurization caused by leaky return ducts can also suck a flame 

out of a water heater, an obvious fire hazard on water heaters 

not equipped with a flame-rollout protective device. These 

more severe situations are not particularly common. However, 

professionals cannot afford to ignore their possible presence, 

because when these problems do occur, they are very serious.

The two main approaches to fixing such problems are to remove 

the source of contaminants and to seal the ducts, especially on 

the return side. Sometimes, it may be helpful to provide outside 

pressure relief or to repair or modify the equipment.

In humid climates, high indoor humidity is one of the most serious 

comfort problems during the cooling season. Often made worse 

by leaky ducts, high humidity can result in mold growth, mildew, 

and wood rot. In addition to damaging the appearance or the 

structural integrity of the building, these organisms can affect the 

health of the occupants if they become airborne. Poor humidity 

control is especially likely when the air is moist and temperature 

levels are moderate. 

When ducts are repaired, rooms at the end of long ducts tend to 

become much more comfortable: warmer in winter and cooler in 

summer. Customers notice this immediate improvement and often 

consider this benefit alone to be worth the entire cost of the repair 

work.

The Golden Opportunity in Ducts

In the United States, ducted heating and cooling systems are 

installed in about 90% of new homes. The prevalence of forcedair systems provides several “golden opportunities” for contractors and builders to provide quality, reliable service to homeowners. 

A golden opportunity is a situation in which a service call to repair

ducts provides exceptionally large reductions in fuel costs, 

increased comfort, enhanced safety, or other forms of customer 

benefits. 

One such golden opportunity is the installation of heat-pump 

systems. In moderate and cold climates, heat pumps rely on 

electric resistance backup heat at the lowest outdoor temperatures, at which the compressor cannot deliver enough heat 

to meet the load. Improved duct efficiency reduces the amount 

of backup heat that the unit must provide. This improves the 

delivered capacity of the heat pump because more of the heating 

energy is delivered to the space rather than to the environment 

outside the home. 

Still another golden opportunity occurs in the southern United 

States. Here, customers often complain that the air-conditioning 

system is not providing adequate cooling. The usual response is 

to install a larger unit. However, the real culprit is often the attic 

duct system. A better solution is to repair the leaking ducts and 

insulate them, which will not only provide a more comfortable 

home environment, but will probably save enough energy to pay 

back the repair cost several times over the life of the equipment.

Jim Cummings, Florida Solar Energy Center/PIX11058

5

In this photo, a Building America staff member performs a duct blaster test to measure the 

impact of duct leakage on whole-house performance.
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From the point of view of the heating, ventilation, and air-conditioning contractor, the single best opportunity to interest a customer in duct renovation occurs when a furnace, heat pump, or 

air conditioner needs to be replaced. Because the contractor is 

already on site, the costs of finding a customer and traveling to 

the job are already paid.

Also, the best choice of replacement unit will often be influenced 

by the condition of the duct system. This provides three 

opportunities: 

• upgraded equipment efficiency, with lower fuel costs

• better duct performance, with still-lower fuel costs and 

improved thermal comfort

• reduction in size and cost of the replacement equipment.

New construction offers many options in the design details of a 

duct system. These choices include location of the duct system 

within the building, the type of system layout, and the level of 

sealing and insulation to be employed. Placing the ducts in the 

conditioned space is the most efficient choice—energy losses can 

be eliminated and health and safety problems are unlikely to arise.

However, at least four impediments stand in the way of widespread use of conditioned-space ductwork: (1) difficulty of hiding 

ductwork, (2) perceived extra cost, (3) need for the building 

designer to get involved with the details of duct design, and 

(4) altered scheduling of trades on the job. 

If any of these difficulties prevent the placement of ducts in the 

conditioned space, the next best practices should be considered. 

Good practice has the following elements:

• design the total heating and cooling system using a reliable 

method, such as that embodied in the Air Conditioning Contractors of America (ACCA) Manuals J, S, and D. An additional 

ACCA manual, “Duct Diagnostics and Repair,” discusses in 

greater detail the issues covered in this brochure

• minimize the surface area of ducts outside the conditioned 

space through good routing, use of low-loss fittings, and 

(where feasible) placement of registers near interior walls 

with the air handler centrally located in an interior closet

• specify suitably low levels of duct air leakage and include a postinstallation leakage test in the construction plan. Air leakage to 

the outside should never exceed 5% of total air flow on either 

the supply or return side

• insulate ducts outside the conditioned space, preferably to R-8.

By combining these elements of good practice, duct energy losses 

can be reduced to a maximum of 20% of the underlying heating 

and cooling loads.

The ACCA Manuals J, S, and D are used for designing total heating 

and cooling systems (see References section). The process begins 

with a load calculation using ACCA Manual J. Manual S uses the 

load information to size the heating and cooling equipment. 

Manual D uses the load and equipment information to size the 

ducts.

Testing and Diagnosing Duct Systems

Visual inspection can reveal some flaws, but many poorly 

performing duct systems look just fine. This is where testing 

comes in. The following are some guidelines for testing and 

diagnosing duct systems.

A trained duct technician can help homeowners save money by maintaining an energyefficient heating and cooling system.

National Association of Technician Excellence (NATE)/PIX11111

6
Step One — Inspect the Duct System

Evaluating a duct system’s efficiency begins with visual inspection. Here are some things to check for: 

• disconnected ducts near registers and where runouts connect 

with trunk ducts

• excessive leaking where some part of the building is used as a 

duct (panned joists, vertical chases, and the like)

• uninsulated ductwork outside the conditioned space. In the case 

of attic ducts, consider adding R-value even if the ducts are 

insulated.

Step Two — Test for Duct Leakage

Duct leakage tests require specialized equipment. At a minimum, 

the contractor needs a duct blower (adjustable calibrated fan) and 

a digital manometer (pressure gauge). 

In the most basic duct leakage test, the duct blower is attached 

to the duct system at a large register or at the air handler, and all 

other registers are sealed. The duct-blower fan is then turned on, 

and its speed is adjusted until the pressure in the ducts reaches 

some standard value. The amount of airflow needed to reach this 

pressure is a measure of the extent of leakage in the ducts. Variations on this technique can obtain more detailed information, such 

as, which side of the duct system (supply or return) leaks more 

and how much of the leakage is to the outside. 

Step Three — Measure the System Airflow Rate

Measuring airflow rate at the system fan is nearly as important as 

measuring duct leakage. The efficiency of the duct system depends 

not on duct leakage alone, but on duct leakage as a fraction of fan 

flow. Another equally important reason is that low fan flow is one 

of the major causes of poor air-conditioner performance. Whatever 

the problem that caused the original call for help, it will usually 

benefit both the contractor and the customer if all problems 

besetting the system can be fixed in the same service call.

Airflow in ducts can be measured by several methods. A recent 

invention called the flow plate speeds up this measurement task 

and is usually accurate to within 7% of the true airflow rate.

Step Four — Determine What Actions to Take

Sometimes, what needs to be done is obvious. At other times, the 

big question is “How much effort should be put into duct repair?” 

Seldom does it pay to reduce duct energy losses all the way to 

zero. Three possible ways to make the decision are rules of 

thumb, program guidelines, and use of a standard to estimate 

the benefits of various corrective actions.

Rules of Thumb — These are very rough attempts to cover 

a wide range of cases, but the following suggestions can be 

adopted when better methods are not available:

Rule 1. Reduce duct leakage until the total duct leakage at 25 

pascals5 pressure is less than 10% of the system fan flow rate.

Rule 2. Add R-8 insulation to any uninsulated ducts in unconditioned spaces and to attic ducts that currently have only R-4. 

Program Guidelines — Residential energy efficiency programs 

run by federal, state, and private-sector agencies are increasingly 

including duct efficiency in their portfolios of system upgrades. In 

the interest of simplicity, these programs often provide their own 

guidelines to be used in assessing the need for duct repairs.

_____________

5

A pascal is a unit of measure that equals one newton per square meter.

The ACCA manuals provide guidelines for designing heating and cooling systems.

Air Conditioning Contractors of America (ACCA)/PIX11113

7
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Standards — ASHRAE Standard 152 provides a means for determining the efficiency of residential duct systems in the heating 

and cooling modes. Although air leakage is a major cause of duct 

inefficiency, other factors such as heat conduction through the 

duct walls, influence of the system fan on pressures within the 

house, and partial regain of lost heat are also important. Standard 152 takes these factors into account. An Internet web site 

(http://ducts.lbl.gov) has an easy-to-use calculator. The user 

enters information about the house, the heating and cooling 

equipment, the system airflow rate, the duct leakage, and the 

name of the city nearest the site. The calculator can then predict 

duct efficiencies for the system.

It’s free, it’s fun (at least for anyone who likes to play with numbers), and it can quickly show the effects of duct location, air 

leakage, and insulation level on duct efficiency. 

Installation and Repair of Duct Systems

When making duct repairs, the contractor has to work with the 

materials at hand. Fortunately, the state of the art in duct repair 

is advancing rapidly.

“Is it OK to use duct tape?” That’s one of the first questions asked 

in a duct repair class. The answer is simple: “A duct repair should 

last as long as the ducts themselves.” Consequently, that rules out 

most types of duct tape that one can normally purchase for duct 

sealing. 

The fabric-backed, rubber-based adhesive duct tape that can be 

bought at the neighborhood hardware store will fail rapidly when 

subjected to the conditions of temperature, humidity, and pressure 

normally encountered in ducts. More advanced tapes, specifically 

designed for duct repair, are coming on the market, and quite 

possibly some may stand the test of time. However, the current 

stance should be, “When in doubt, don’t use it.”

So, what do we recommend? This depends on the material from 

which the duct is constructed, but the best general answer is a 

special UL Listed (not just UL Classified) adhesive paste called 

mastic (preferably one that is specially formulated for duct repair). 

UL Classified mastic tests mainly for problems relating to fire, 

whereas UL Listed mastic tests for many things, of which the 

most important for our purposes is co-adhesion (holding ability 

and elasticity).

Sealing — The proper sealing procedure for smaller leaks (less 

than 1/4 in. wide) is to apply a bead of mastic alone. For larger 

gaps, first apply a layer of mastic at least 3 in. wide along the 

entire crack length. Then embed a layer of fiberglass mesh at 

least 2 in. wide in the mastic, and then apply a final layer of 

mastic over the mesh. Proper technique is best learned from 

an experienced practitioner. The process is not difficult, though 

sometimes it is awkward.

When repairing ducts, plan the job. Remember that the tasks of 

sealing and insulating the ducts are equally important. A wellplanned job will include the following steps:

Duct leakage can be tested using an adjustable fan and a digital pressure gauge.

Charlie Castillega/PIX09808

8
• sketch the duct system

• evaluate the fundamental integrity of the duct system

• seal the ducts

• insulate the ducts

• correct zone pressure imbalance problems.

After doing an evaluation of the duct system, it may be advisable 

to replace one or more duct sections. This is especially true in the 

following situations:

• the structural integrity of the duct system has been seriously 

compromised

• parts of the building have been used as ducts in such a manner 

as to make sealing excessively difficult or of questionable value

• replacement is less costly than repair.

The decision to repair or replace will often be strongly influenced 

by economics. For example, flex duct is relatively quick and cheap 

to install; sheet metal and duct board are more involved. Once 

replacements have been made, the ducts can be sealed.

Duct sealing can be divided into two portions:

• repairing large leaks found during the general inspection

• finding and repairing other leaks.

Large leaks are usually disconnected ducts. Sometimes the physical reconnection will be relatively simple. At other times, the 

disconnect will be caused by failure of some component, which 

will have to be replaced. Once the large leak is repaired, the total 

leakage around the remaining cracks and spaces in the joint can 

be treated as smaller leaks, along with any previously found holes 

that are not disconnects.

After all known leaks are sealed, it’s time to seek out the less 

obvious ones. This is vital because most systems have sections 

that are not easy to see, and leaks can be easily overlooked.

A small hand-held smoke generator is a handy tool for this job. 

Introduce the smoke at the inlet side of the duct-blower fan and 

watch to see where it exits. Be certain, of course, that the smoke 

used is of acceptably low toxicity and that the house is well 

ventilated during and after the test.

Insulating — Insulating the ducts is the second part of the ductrepair job. Duct board and flexible ducts are usually provided with 

effective R-values ranging from R4 to R8. 

Sheet-metal ducts may be insulated or uninsulated. In either case, 

additional insulation can be added in the form of duct wrap. 

Pressure Testing — Because pressure imbalances can have 

serious health and safety implications in some systems, it is 

imperative that technicians learn proper pressure-testing techniques. Zone pressurization testing has two distinct goals. The 

first, and most important, is testing for worst-case depressurization of a room or zone containing combustion appliances. 

As a rule, such an area of the building should not be allowed 

to depressurize more than 3 pascals relative to the outside.

The second goal is to look for pressure differences between zones 

that can be separated by closing a door. Pressure differences of 

more than 2 to 3 pascals should be relieved by providing an adequate airflow path between the zones. 

Training — Any duct retrofit business worthy of the name will 

require its technicians to receive hands-on training at a good 

duct-repair school. Periodic updating of technique is also highly 

recommended. Aside from the basic hand-sealing technique, 

Repair of a platform return. Before (top): 

Note the cracks and gaps along the 

edges and joints. After (right): The same 

platform return after it has been sealed 

from the inside using mastic.

Jim Cummings, FSEC/PIX11056

Jim Cummings, FSEC/PIX11055

9
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practitioners should keep abreast of new technologies of automatic duct sealing. One of these methods makes use of aerosol 

sealants blown into the duct with a computer-controlled 

adjustable-speed fan.

We hope that this brochure helps you to better understand home 

heating and cooling ducts and the problems that can arise, as 

well as their solutions. The following section provides a list of 

resources for additional information pertaining to ducts.

References, Resources, and Additional Information

This brochure has been condensed from a larger publication. See 

page 1 of this brochure for information on how to get a copy. The 

following references may also be useful:

Publications

Duct Basics

Home Energy Magazine. 1993. Special Issue — Ducts Rediscovered. September/October.

This Old House: Heating, Ventilation, and Air Conditioning, by 

Richard Trethwey. Little, Brown. 1994.

Right-Size Heating and Cooling Equipment. January 2002. 

U.S. Department of Energy, Office of Building Technology, 

State and Community Programs, DOE/GO-102002-1490.

Health, Safety, and Comfort Issues in Residential Ducts

Home Energy Magazine. 1997. Special Issue — Health and Safety. 

November/December. 

Fire Safety Standards

NFPA-31. Standard for the Installation of Oil-Burning Equipment

NFPA-54. National Fuel Gas Code

NFPA-211. Chimneys, Fireplaces, Vents, and Solid Fuel-Burning 

Appliances

National Fire Protection Association, 1 Batterymarch Park, 

Quincy, Massachusetts 02269-9101.

Customer Benefits from Better Duct Systems

A Builder’s Guide to Placement of Ducts and HVAC Equipment in 

Conditioned Spaces. NAHB Research Center, Inc., 400 Prince 

George’s Blvd., Upper Marlboro, Maryland 20774.

Designing and Building Interior Duct Systems. Florida Solar 

Energy Center, 1679 Clearlake Road, Cocoa, Florida 32922.

Duct Design Strategies

Delivering Tons to the Register: Energy Efficient Design and 

Operation of Residential Cooling Systems, by J. Siegel, I. Walker, 

and M. Sherman. Proceedings of the 2000 ACEEE Summer Study 

on Energy Efficiency in Buildings. Vol. 1, pp. 295–306.

Reputable heating and cooling businesses will require their duct technicians to attend 

training courses to stay informed of the latest techniques.

National Association of Technician Excellence (NATE)/PIX11112

10
Energy Efficient Design of New Low-Rise Residential Buildings. 

Standard 90.2-1993. American Society of Heating, Refrigerating, 

and Air-Conditioning Engineers, 1791 Tullie Circle, N.E., Atlanta, 

Georgia 30329.

Residential Design Manuals

Manual J: Residential Load Calculation

Manual S: Residential Equipment Selection

Manual D: Residential Duct Systems

Air Conditioning Contractors of America, 2800 Shirlington Road, 

Suite 300, Arlington, Virginia 22206.

Testing and Diagnosing Duct Systems

ASHRAE Standard 152P: Method of Test for Determining the 

Design and Seasonal Efficiencies of Residential Thermal 

Distribution Systems. American Society of Heating, Refrigerating, 

and Air Conditioning Engineers, 1791 Tullie Circle, N.E., Atlanta, 

Georgia 30329.

A New Device for Field Measurement of Air Handler Flows, by 

L. Palmiter and P. W. Francisco. Proceedings of the 2000 ACEEE 

Summer Study on Energy Efficiency in Buildings. Vol. 1, 

pp. 197–206.

Installation and Repair of Duct Systems

A Guide to Insulated Air Duct Systems. North American Insulation 

Manufacturers Association, 44 Canal Center Plaza, Suite 310, 

Alexandria, Virginia 22314.

Flexible Duct Performance and Installations Standards, 3rd Edition. 

Air Diffusion Council, 1000 E. Woodfield Road, 

Suite 102, Schaumburg, Illinois 60173-5921.

Installation Standards for Residential Heating and Air Conditioning 

Systems. Sheet Metal and Air Conditioning Contractors National 

Association, Inc., 4201 Lafayette Center Drive, Chantilly, Virginia 

20151-1209.

Residential Duct Diagnostics and Repair. Air Conditioning Contractors of America, 2300 Shirlington Road, Suite 300, Arlington, 

Virginia 22206.

Residential Field Testing of an Aerosol-Based Technology for Sealing Ductwork, by M. P. Modera, D. Dickerhoff, and O. Nilssen. 

Proceedings of the 1996 ACEEE Summer Study on Energy Efficiency in Buildings. Vol. 1, pp. 169–176.

Stopping Duct Quacks: Longevity of Residential Duct Sealants, by 

M. Sherman, I. Walker, and D. Dickerhoff. Proceedings of the 2000 

ACEEE Summer Study on Energy Efficiency in Buildings. Vol. 1, 

pp. 273–284.

Web Links

Home Energy Magazine 

www.homeenergy.org/

An Introduction to Residential Duct Systems 

ducts.lbl.gov/

Air Conditioning Contractors of America 

www.acca.org/

Affordable Comfort, Inc. 

www.affordablecomfort.org/

North American Technician Excellence 

www.natex.org/

United States Environmental Protection Agency Energy Star 

energystar.gov/ducts/

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Bringing you a prosperous future where energy is clean, abundant, reliable, and affordable

A Strong Energy Portfolio 

for a Strong America

Energy effi ciency and clean, renewable 

energy will mean a stronger economy, 

a cleaner environment, and greater 

energy independence for America. 

Working with a wide array of state, 

community, industry, and university 

partners, the U.S. Department of 

Energy’s Offi ce of Energy Effi ciency 

and Renewable Energy invests in a 

diverse portfolio of energy technologies.

Research and Development 

of Buildings

Our nation’s buildings consume more 

energy than any other sector of the 

U.S. economy, including transportation 

and industry. Fortunately, the opportunities to reduce building energy use—

and the associated environmental 

impacts—are signifi cant.

DOE’s Building Technologies Program 

works to improve the energy effi ciency 

of our nation’s buildings through innovative new technologies and better 

building practices. The program

focuses on two key areas:

• Emerging Technologies 

Research and development of the 

next generation of energy-effi cient 

components, materials, and 

equipment

• Technology Integration

Integration of new technologies 

with innovative building methods 

to optimize building performance 

and savings

For more information contact:

EERE Information Center

1-877-EERE-INF (1-877-337-3463)

www.eere.energy.gov

An electronic copy of this factsheet is 

available on the Building America Web 

site at www.buildingamerica.gov

U.S. Department of Energy

Energy Effi ciency

and Renewable Energy

Building America Program

George S. James • New Construction • 202-586-9472 • fax: 202-586-8134 • e-mail: George.James@ee.doe.gov

Terry Logee • Existing Homes • 202-586-1689 • fax: 202-586-4617 • e-mail: terry.logee@ee.doe.gov

Lew Pratsch • Integrated Onsite Power • 202-586-1512 • fax: 202-586-8185 • e-mail: Lew.Pratsch@hq.doe.gov

Building America Program • Offi ce of Building Technologies, EE-2J • U.S. Department of Energy • 1000 Independence Avenue, S.W. • 

Washington, D.C. 20585-0121 • www.buildingamerica.gov

Building Industry Research Alliance (BIRA)

Robert Hammon • ConSol • 7407 Tam O’Shanter Drive #200 • Stockton, CA 95210-3370 • 209-473-5000 • fax: 209-474-0817 • 

e-mail: Rob@consol.ws • www.bira.ws

Building Science Consortium (BSC)

Betsy Pettit • Building Science Consortium (BSC) • 70 Main Street • Westford, MA 01886 • 978-589-5100 • fax: 978-589-5103 • 

e-mail: Betsy@buildingscience.com • www.buildingscience.com

Consortium for Advanced Residential Buildings (CARB)

Steven Winter • Steven Winter Associates, Inc. • 50 Washington Street • Norwalk, CT 06854 • 203-857-0200 • fax: 203-852-0741 • 

e-mail: swinter@swinter.com • www.carb-swa.com

Davis Energy Group

David Springer • Davis Energy Group • 123 C Street • Davis, CA 95616 • 530-753-1100 • fax: 530-753-4125 •

e-mail: springer@davisenergy.com • deg@davisenergy.com • www.davisenergy.com/index.html

IBACOS Consortium

Brad Oberg • IBACOS Consortium • 2214 Liberty Avenue • Pittsburgh, PA 15222 • 412-765-3664 • fax: 412-765-3738 •

e-mail: boberg@ibacos.com • www.ibacos.com

Industrialized Housing Partnership (IHP)

Subrato Chandra • Florida Solar Energy Center • 1679 Clearlake Road • Cocoa, FL 32922 • 321-638-1412 • fax: 321-638-1439 • 

e-mail: subrato@fsec.ucf.edu • www.baihp.org

National Association of Home Builders (NAHB) Research Center

Tom Kenney • National Association of Home Builders (NAHB) Research Center • 400 Prince George’s Boulevard • 

Upper Marlboro, MD 20774 • 301-430-6246 • fax: 301-430-6180 • toll-free: 800-638-8556 • www.nahbrc.org/ 

National Renewable Energy Laboratory

Ren Anderson • 1617 Cole Boulevard, MS-2722 • Golden, CO 80401 • 303-384-7433 • fax: 303-384-7540 • 

e-mail: ren_anderson@nrel.gov • www.nrel.gov

Tim Merrigan • 1617 Cole Boulevard, MS-2722 • Golden, CO 80401 • 303-384-7349 • fax: 303-384-7540 • 

e-mail: tim_merrigan@nrel.gov • www.nrel.gov

Oak Ridge National Laboratory

Pat M. Love • P.O. Box 2008 • One Bethel Valley Road • Oak Ridge, TN 37831 • 865-574-4346 • fax: 865-574-9331 • 

e-mail: lovepm@ornl.gov • www.ornl.gov

Produced for the U.S. Department of Energy (DOE) by the National Renewable Energy Laboratory, a DOE national laboratory.

November 2004 • DOE/GO-102004-1606

Printed with a renewable-source ink on paper containing at least 50% wastepaper, including 20% postconsumer waste.

Visit our Web sites at:

www.buildingamerica.gov www.pathnet.org www.energystar.gov

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