This section provides simple strategies and solutions to improve the comfort, energy efficiency, and
environmental performance of your home by addressing "whole-house" issues, such as heating and cooling,
lighting, insulation and air sealing, and windows and doors. Additional whole-house topics discussed
include hot water heating, interior walls and ceilings, air cleaning, exterior finishes, and green
- Heating and Cooling
- Insulation, Air Sealing, and Weatherization
- Windows, Skylights, and Exterior Doors
- Hot Water Systems
- Interior Walls and Ceilings
- Air Cleaning
- Exterior Finishes
- Green Power for the Home
Heating and Cooling Systems
Heating and cooling costs are typically the largest energy expense for most U.S. homes. You have a
wide variety of available options to improve the energy efficiency of your heating and cooling system.
Simple changes, such as sealing air ducts and installing a programmable thermostat can improve the
efficiency of your system and save you money on utility bills. In some cases, simply replacing your
system all together may be the most cost effective and energy efficient choice. When looking for
ways to improve the efficiency of your heating and cooling system, consider these options:
- Install a new energy efficient heating and cooling system
- If you are looking for new heating or cooling equipment, look for equipment labeled ENERGY STAR.
Replacing your old heating and cooling equipment with new, energy-efficient models is a great start.
But to make sure that you get the best performance, the new equipment must be properly installed.
In fact, improper installation can reduce system efficiency by up to 30 percent - costing you more
on your utility bills and possibly shortening the equipment's life.
For more information on ENERGY STAR heating and cooling systems, download ENERGY STAR's Guide to Energy Efficient Heating & Cooling at:
- Regular maintenance
- Annual maintenance is a must for a well performing heating and cooling system.
Clean your filter regularly and schedule annual maintenance by a qualified contractor.
- Programmable thermostat
- A programmable thermostat is one of the easiest ways you can save energy in your home.
An ENERGY STAR qualified programmable thermostat helps make it easy for you to save by
offering four pre-programmed settings to regulate your home's temperature in both summer
and winter - when you are asleep or away.
For more information on programmable thermostats, go to:
- Duct sealing
- In houses with forced-air heating and cooling systems, ducts distribute conditioned air throughout the house.
In a typical house, however, about 20 percent of the air that moves through the duct system is lost due to
leaks and poorly sealed connections. The result is higher utility bills and difficulty keeping the house
comfortable, no matter how the thermostat is set. Sealing those leaks in the ducts is a must to get
better performance from your heating and cooling system. In addition, insulating ducts in unconditioned
spaces that get especially hot in summer or cold in winter (such as attics, garages, or crawlspaces) can
save significant energy.
For more detailed information about the importance of sealing ducts, go to:
- Heating and cooling only those portions of your house you use
- This can reduce fuel consumption, conserve energy and save you dollars while maintaining comfort.
However, in using this strategy there can be potential negative side effects that must be avoided.
If there are areas of your house you don't need to use often, you can close vents and air registers to
them and direct the heating or cooling to the portions of the home where you spend most of your time.
Homes with central heating and cooling can benefit the most from this technique. For example, during
the winter consider directing more of the heat to the family or living room if that is where you spend
most of your time. If rooms are not used, you can close air registers and doors and confine heated or
cooled air to the areas where you need it most. Note in winter, that the cooler parts of your home will
still need to be heated to above freezing to avoid freezing pipes. Also, with some HVAC systems,
especially those that are already high- performance, efficient systems, closing too many vents or
registers may imbalance the entire heating and cooling system and actually make the system run
less efficiently. In addition, moisture problems need to be avoided where certain rooms or
areas of a house are not getting dehumidified air.
- Geothermal heating/cooling
- The Earth's heat, called geothermal energy, constantly flows outward from its core and can provide a
useful supplement for heating and cooling. Unfortunately, many people think you have to live over a
hotspring, a geyser or some other intense source of geothermal heat to be able to make use of this
source, but this is far from the truth. You can use geothermal energy-no matter where you live in
the United States-to heat and cool your home by using a ground-source heat pump.
For more information on the potential for geothermal heating/cooling in your home, go to:
Providing fresh air flow into a house is a low-cost and potentially energy-efficient way to cool a home and
maintain good indoor air quality. In good weather, natural ventilation (when air moves through windows or doors)
can suffice for cooling. On some days, the air temperature at night is pleasantly cool and letting this air
into the house during the night can significantly cool down a house after a warm day. Natural fresh air
ventilation can also be supplemented by a number of low-energy mechanical ventilation devices that can help.
- Ceiling fans
- Ceiling fans are a useful alternative to help keep you cool while reducing or eliminating the need to
use air conditioning. Typically a ceiling fan consumes much less electricity than does a central air
conditioner. A ceiling fan doesn't cool or de-humidify a room - it only cools you through a wind-chill
effect against your skin. Ceiling fans are also inexpensive to purchase. Make sure, however, to turn
your fan off when you leave the room. If you are not there to feel the cooling air movement on your skin,
continuing to operate the fan only wastes energy.
- Window fans
- Window fans can also help to cool down your house in lieu of running your central air conditioning.
A box fan, or other type, placed in an open window can blow cooler outside air into a room, or set in
reverse, can draw cool air in through other windows and throughout the entire house. This, of course,
is best done when the air outside has cooled down, such as in the evening, yet the air inside the house
is still warm. Humidity conditions, pollen, dust and other factors will need to be considered when using
this approach. A window fan, or portal box fan or fan on a stand can also be used in a fashion similar to
a ceiling fan to blow air against your skin to create a wind chill cooling effect.
- Whole-house fans
- Whole-house fans help cool your home by pulling cool air through the house and exhausting warm air out
of the house. Typically these are very large fans installed by professionals in the attic of a home.
They are most effective when operated at night and when the outside air is cooler than inside. However,
allowing them to continue to run when outdoor temperatures are hotter than indoors, defeats the purpose
and will waste energy. Again, humidity conditions, pollen, dust and other factors will need to be
considered when deciding to use this approach.
For more information on cooling your home through fresh air ventilation techniques, go to:
Air Conditioning (AC)
Air conditioners use about 5 percent of all the electricity produced in the United States, at a cost of over
$11 billion to homeowners. As a result, roughly 100 million tons of carbon dioxide are released into the air
each year-an average of about two tons for each home with an air conditioner. Thus, an environmentally
preferable approach is to use other cooling strategies before air conditioning, such as ceiling fans or
window fans discussed above. However, depending on where you live, there will be times when it is too
hot or humid, or pollen levels are very high, for cooling methods discussed above to be effective.
As such, air conditioning may be necessity for your home. If you decide to air condition your home,
consider whether room units or central air is a better strategy by reading the information below, and
purchase the correct unit size of an ENERGY STAR air conditioner.
- Room units
- If you only need to cool certain areas of the house, room (or window) units may be the best
air conditioning choice. Room air conditioners offer you the opportunity to cool your home in "zones,"
so they are less expensive to operate than central units, even though their efficiency is generally
lower than that of central air conditioners. If there are rooms that do not need to remain cool
consistently, keep the doors closed and the air conditioner off to save more energy.
For more information on ENERGY STAR Room air conditioners, go to:
- Central air
- When buying a new central air conditioner, make sure it is properly sized and installed-bigger is not always
better. Units with too large a capacity will cost you more and may decrease your home's comfort.
Hire a qualified, licensed contractor who uses Manual J or an equivalent size-calculation tool.
Look for a model with a high Seasonal Energy Efficiency Ratio (SEER), which measures the seasonal
or annual efficiency of a central air conditioner. The higher the SEER, the more energy efficient
the system. ENERGY STAR qualified central air conditioners have a higher seasonal efficiency
rating (SEER) than standard models, which makes them about 14 percent more efficient than
standard models on average.
For more information on ENERGY STAR central air conditioners, go to:
If your air conditioning equipment is more than 10 years old, it may be time for a more energy-efficient replacement. ENERGY STAR qualified air conditioners offer significant long-term energy savings compared with 10-year-old units, and use at least 20 percent less energy than new standard models.
When you use air conditioning, it is important to make sure windows are closed. It makes no sense to air condition (or heat) a house with a window open! Given this, fresh air cooling takes some attention and diligence to do it right.
For additional information on air conditioning, go to:
Passive Solar Heating and Cooling
While home construction can incorporate many technologies to help homeowners save energy, there are additional
measures you can design into your home to take advantage of solar energy without installing solar collectors
on your roof. Some existing homes can also take advantage of passive solar heating. Buildings that use
passive solar design need fewer or smaller-scale active technologies to meet the remainder of their
heating and lighting needs (i.e., smaller mechanical heating systems). Because the sun's energy is
free, maximizing use of passive solar techniques before adding active technologies can significantly
reduce your energy bills. Work with your architect to incorporate the following into your blueprints.
Design elements of passive solar heating and cooling include:
House orientation (south-facing windows).
Vegetation/trees for shading and wind breaks.
Another simple strategy is to plant deciduous trees near south, east, and west-facing windows,
which will provide needed shade in the summer, but let in the sun's heat during the winter
(when the leaves have fallen). Also, evergreen trees on the north side of your home can
help buffer winter winds.
Use the sun's heat - During the heating season, open curtains on your south or west-facing windows during
the day to allow sunlight to naturally heat your home, and close them at night to reduce any chill.
During the cooling season, keep your window coverings closed during the day to prevent solar gain.
Thermal mass materials - These materials retain or store heat produced by sunlight or other sources.
They are typically dense materials such as stone, concrete, or metal, and are often an important
component of solar heating systems and other high efficiency systems.
- When building a new home or planning a major addition, consider orienting windows to the south. You can also use roof overhangs to help reduce energy use by providing shade from the sun in the summer and solar heat gain in the winter
For more information on passive solar heating and how it works, go to:
Supplemental Heating Sources
Homeowners may enhance their existing heating capabilities through the use of supplemental heating sources.
If you use or are thinking of purchasing a supplemental heating source, consider the following:
- Wood stoves
- A wood stove can be a significant source of supplemental heat in your home and another way for you
to save money on your energy bills. Today's wood stove models feature improved safety, efficiency
and lower emissions. If installed and operated correctly, they produce almost no smoke, minimal
ash, and require less firewood than older models. They can be sized to heat a family room, a
small cottage, or a full-sized home.
However, woodstoves take time and effort and a steady supply of wood for fuel. If you buy it, firewood can be expensive in some locations and a chore to store and transport into the house. Wood stored inside the house can lead to insect problems. Wood stoves need considerable attention to ignite and operate correctly and the ashes need to be carefully cleaned out periodically, which can be a messy job. If not operated correctly, wood stoves can generate smoke and other pollutants that can lead to poor indoor air quality.
For more information to help you choose an EPA certified wood stove or fireplace insert, or another cleaner burning hearth appliance (e.g., gas or pellet stove), go to:
- Fireplaces are not very energy efficient. Although a fire in an open fireplace may provide ambience,
an open fireplace typically draws more heat out of a house than it provides. To save energy, keep
your fireplace damper closed unless a fire is going. Keeping the damper open is like keeping a
window wide open during the winter; it allows warm air to go right up the chimney. When you use
the fireplace, turn down your thermostat for the rooms warmed by the fire.
- Active solar heating - Supplemental heating can be provided by active solar technologies. Small scale solar space heating systems often use a solar collector that concentrates heat in either a liquid or in the air which is then distributed throughout the home. Active solar heating systems are cost-effective when they are used for a large part of the year, that is, in cold climates with good solar resources. They are most economical when displacing more expensive heating fuels, such as electricity, propane, and oil heat. Certain tax credits are also available for solar home heating technologies.
There are many ways you can reduce electricity use in your home and help reduce your energy bills,
including using natural lighting strategies, selecting energy-efficient light bulbs and fixtures,
and installing lighting controls to automatically turn lights on and off.
- ENERGY STAR lighting bulbs and fixtures
- Learn about energy efficient light bulbs, fixtures (across a range of technologies),
and decorative light strings (holiday lights).
For more information on choosing energy efficient lighting, go to:
- Lighting controls
- Lighting controls can be used to automatically turn lights on and off as needed, preventing energy waste.
The most common types of lighting controls include motion or occupancy sensors, photosensors, timers,
For more information on lighting control options, go to:
- You can increase the energy efficiency and reduce the climate impact of your home by taking advantage of
the natural light windows and skylights can bring in, often referred to as "daylighting."
Daylighting is simply the use of natural sunlight to brighten up and warm a home's interior.
Today's highly energy-efficient windows, as well as advances in lighting design, allow for windows to
reduce the need for artificial lighting during daylight hours without causing heating or cooling problems.
The more natural light available, the less you have to rely on energy to run light fixtures. Daylighting
also helps improve your home's aesthetic feel. Using light-colored wall paints can also help brighten
up a room and reflect more daylight throughout the space.
For more information on daylighting, go to:
Properly insulating your home is one of the most effective steps you can take to keep your home warm in the winter and cool in the summer. There are several types of insulation - e.g., fiberglass, cellulose, recycled cotton batts, rigid foam board, and spray foam. Reflective insulation (or radiant barrier) is another insulating product which can help save energy in hot, sunny climates. When correctly installed, each type of insulation can deliver comfort and lower energy bills during the hottest and coldest times of the year.
Insulation is measured by an R-value - the higher the R-value, the greater the insulating capacity of the material. Colder climates require higher R-value insulation to ensure that less heat is lost through the walls and ceilings of your home. In addition, insulation will also help keep the cool air inside during the warm weather.
For information on recommended R-values for homes in your area, go to:
If you are building a new home, you may consider installing a super insulating wall system,
which include the following technologies and components:
- Conventional framing with rigid sheathing
- This wall system uses conventional framing and insulation between the studs, but with a complete
air barrier formed on the outside with rigid insulation.
- Double framed walls
- Two sets of conventionally framed walls are constructed with offset vertical framing. This framing
eliminates thermal bridging except at the top and bottom plates. This type of framing allows room for
additional insulation for increased R-Value.
- Structural insulated panels
- Structural insulated panels (SIPs) are prefabricated insulated structural panels for use in
building walls, ceilings, floors, and roofs. They provide superior and uniform insulation compared to
more traditional construction methods (stud or "stick frame"), offering energy savings of 12-14 percent.
- Insolating concrete forms
- Homes built using an insulating concrete form (ICF) system literally have the insulation built into
the walls as part of the structure. This system creates walls that have a high thermal resistance, with
R-values typically above R-17. Even though ICF homes are constructed using concrete, they can look just
like traditional stick-built homes.
For more information on super insulating systems, go to:
Your home's envelope - the outer walls, ceilings, windows, doors and floors - may be letting too much air into or out of the home. Hidden gaps and cracks in a home can create as much airflow as an open window, and can cause your heating and cooling systems to work harder. Sealing coupled with insulating your home's shell is often the most cost effective way to improve energy efficiency and comfort.
Download the Do-it-yourself Guide to Sealing and Insulating with ENERGY STAR to better understand the importance of air sealing and insulating and key steps to sealing and insulating your home.
For more information on air sealing, go to:
Weatherization refers to cost-effective energy efficiency measures that address heat losses from the building envelope, heating and cooling systems, electrical system, and electricity consuming appliances. Some common weatherization techniques for windows and doors include caulking and weatherstripping leaky areas, and installing storm doors and windows
Windows, skylights, and exterior doors can be some of your home's most attractive features. They provide views, daylighting, ventilation, and solar heating in the winter. Windows, doors, and skylights can also account for a significant percentage of your heating bill in the winter, as cold air can infiltrate into the home through leaky windows and warm air escapes, making your heating system run more. And during the summer, your air conditioner must work harder to cool hot air from sunny windows. If you are replacing or installing windows, doors or skylights, you can reduce energy costs by installing energy-efficient windows, doors, and skylights in your home. When purchasing new windows, doors, or skylights, look for the ENERGY STAR label.
For more information on energy efficient windows, doors, and skylights,
including information on energy rating systems, go to:
Water heating is the third largest energy expense in your home. It typically accounts for about 13% of your utility bill, and can account for 14%-25% of the energy consumed in your home. You can reduce your monthly water heating bills by selecting the appropriate water heater for your home or pool-such as tankless, heat pump, or solar hot water heaters-and by using some energy-efficient water heating strategies.
If your water heater's tank leaks, you may need a new water heater. If you are not in the market for a
new hot water heater, consider installing an insulation blanket on your water heater tank, and insulate
at least the first 3 to 6 feet of the hot and cold water pipes connected to the water heater.
When installing a hot water heater insulation blanket:
- For electric hot-water storage tanks, be careful not to cover the thermostat.
- For natural gas or oil hot-water storage tanks, be careful not to cover the water heater's top, bottom, thermostat, or burner compartment.
- Always make sure to follow the manufacturer's recommendations
These strategies will help get hot water to you faster, saving thousands of gallons of water per year in each household.
For more information on energy efficient hot water heaters, including how they work and whether one might
be right for your home, go to:
In addition, one of the easiest ways to cut your water heating bills is to insulate your hot and cold water pipes.
For more information on hot water heater and pipe insulation, go to:
The interior walls and ceilings of your home provide a surface to add decorative wall finish. There
are choices you can make in the products and materials you use to limit the amount of harmful
chemicals you are exposed to.
- Lead based paint
- Special care should be taken when sanding a surface to prepare for painting due to the dust released into the
air. The dust may contain lead particles, if the surface contains lead-based paint. Lead has long been
recognized as a harmful environmental pollutant, and is a particular concern for children's health and
intellectual development. In homes, old lead-based paint is the most significant source of lead exposure
in the U.S. today, particularly those homes built before 1978, when lead-based paint was phased out.
Lead-based paint that is in good condition is usually not a hazard. However, lead from paint chips,
which you can see, and lead dust, which you can't always see, can be serious hazards. Peeling,
chipping, chalking, or cracking lead-based paint can be a hazard for children and pets who ingest
flakes of lead paint from the floor, or from surfaces that children can chew or that get a lot of
wear-and-tear. These include windows and window sills; doors and door frames; stairs, railings,
and banisters; and porches and fences. Also, lead dust can form when lead-based paint is dry scraped,
dry sanded, heated, or when painted surfaces bump or rub together. Settled lead dust can re-enter the
air when people vacuum, sweep, or walk through it.
If your home has lead-based paint, you can also be exposed to it when remodeling. It is important to keep the remodeling work, and dust associated with the work, separated from other areas in the home. On April 22, 2008, EPA issued a rule requiring the use of lead-safe practices and other actions aimed at preventing lead poisoning from renovation and other activities. Under the rule, beginning in April 2010, contractors performing renovation, repair and painting projects that disturb lead-based paint in homes, child care facilities, and schools built before 1978 must be certified and must follow specific work practices to prevent lead contamination. You should ask your contractor for proof of certification prior to the start of any remodeling, repair, or painting work that will disturb paint in pre-1978 housing or child care facilities.
For more information about preventing lead exposure in your home, go to:
- Volatile Organic Compounds (VOCs)
- VOCs are emitted by a wide array of products including many: paints and lacquers, paint strippers, adhesives,
and solvents. Some VOCs contribute to outdoor smog, as well as indoor air pollution. When choosing paint,
look for no- or low-VOC products. Should you decide on paint that contains even a small amount of VOCs,
make sure to properly ventilate your home when applying the product. If using wallpaper, be aware that
self stick wall coverings typically have higher VOC content that traditional wallpaper paper paste.
For more information on painting and indoor air quality in your home, go to:
Air cleaning devices such as mechanical filters, electronic air cleaners, and ion generators can help improve indoor air quality. However, alone they cannot assure adequate air quality, and should be used in conjunction with chemical reduction strategies and proper home ventilation. The effectiveness of air cleaners in removing pollutants from the air depends on the device's efficiency and the amount of air it handles.
For more information on air cleaning devices, go to:
The exterior finish of your house adds aesthetic appeal to your home, and also prevents air infiltration and water damage. When choosing the finish for your home, look into recycled-content materials that are locally manufactured. High-maintenance materials (such as wood) should be avoided to reduce repair, replacement, and upkeep costs (e.g., repainting). Brick, concrete, stucco, steel, aluminum, and fiber-cement offer superior longevity, and resist cracking and other deterioration. If you use paint on the exterior of your home, consider low-VOC products to reduce air pollution.
Home electricity is a significant source of air pollution and greenhouse gas emissions in many regions, as fully half of the electricity generated in the U.S. comes from burning coal, which emits significant air pollutants and greenhouse gases. Buying green power can help reduce your home's environmental impact while also providing a number of other valuable benefits. Green power is produced from a subset of renewable resources, such as solar, wind, geothermal, biomass, and low-impact hydropower.
Homeowners can purchase green power through three options:
- Green power utility products
- Homeowners can check with their local electricity service provider to see if they offer a green power product.
Currently, more than 850 utilities, or about 25 percent of utilities nationally, offer green power products
to customers. These products allow customers to purchase some portion of their electricity from renewable
resources-almost always at a higher price, but sometimes offered with price-hedging benefits.
- Renewable energy certificates
- Regardless of whether a homeowner's utility offers a green power product, any consumer in the U.S.
can buy green power through renewable energy certificates, also known as RECs. RECs are the environmental
benefits associated with renewable energy generation and are sold by renewable energy certificate marketers
and are separate from your existing electricity service. Homeowners can use EPA's Green Power Locator to
find a list of local utilities and renewable energy certificate marketers that sell green power products
in their state.
For more information on RECs, go to:
- On-site generation
- A homeowner can also investigate the option of installing an onsite energy generation system on their
residence. On-site energy generation systems
include such systems as photovoltaics (solar panels), wind
generators, and other types of renewable energy technologies. Combining on-site renewable energy generation
with energy efficiency improvements that reduce a home's energy load helps ensure that an installed system
is properly sized. Further, the energy cost savings produced by energy efficiency improvements can be used
to offset the purchase and installation costs of renewable energy generation systems and thus shorten
On-site renewables provide advantages of reliability and price stability. In addition, when on-site renewables generate more power than is needed on site, many states allow the excess power to be returned to the electric grid for credit from the local electric utility. This process is known as net-metering. A variety of tax credits are available for on-site generation systems at the federal level; additional incentives are available from some states and localities.
For more information on solar electricity for your home and incentive programs, go to:
For more information on solar electricity for your home and incentive programs, go to: