An energy-efficient home reduces maintenance and utility costs. It can also improve durability, lessen noise, and make you more comfortable.
You can integrate energy-efficient equipment and practices into new homes or retrofit them into your existing one. Further, with how diverse energy efficiency improvements are, if one technique or strategy is unfeasible for your home, there are many more solutions you can use elsewhere.
Energy-Efficient Techniques for New Construction
With new construction, you can design and build an energy-efficient home from the ground up. If you’re feeling particularly ambitious and have the resources, you can even try for net-zero energy project that consumes only as much energy as it generates (or less.)
Watch this video for a quick recap of how to build an energy-efficient building.
Want more details on the latest energy news for homeowners? Read our facts and statistics guide for energy-efficient homeowners.
Site Selection and Placement
Energy efficiency starts with site selection. By building near existing infrastructure, you can save money, resources, and energy in turn.
When selecting a site, you should also consider what’s around your home. If you find a home where local shopping or public transit are nearby, it’s easier to save fuel.
Design Considerations
The best way to create an energy-efficient home is to use a whole-building systems approach. This approach treats the home as one energy system with separate parts that depend on each other. It’s the same approach used for ENERGY STAR requirements, Leadership in Energy and Environmental Design (LEED) standards, and the International Green Construction Code (IgCC).
A house’s material footprint in the moment is one part of the whole-building approach. Your home design should make efficient use of water, power, and other natural resources, and by making it a little smaller, you can minimize waste and materials.
However, that’s only one part of the picture. You should ask yourself these questions as you plan your future home:
- Does the design easily allow for future retrofits without impacting the house’s performance?
- Will the home be oriented properly on the lot, and will windows, rooflines, and other features be in the right spots for efficiency?
- Does the design minimize use of land, water, energy, and raw materials?
Architects and contractors can use special energy modeling software to predict a building’s energy use over time. These results can help you optimize your home’s performance and cost before construction starts.
Building Walls for Energy Efficiency
A home’s walls play a crucial role in its energy efficiency. Properly insulating them helps lower heat loss, and building them from the right materials can help you get more from less resources. Follow these tips:
- Use continuous insulation: A continuous layer of insulation (CI) around the building envelope is essential to an energy-efficient building. Continuous insulation increases the effective R-value of the structure, eliminates condensation, and creates a comfortable space for the building’s occupants. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE 90.1) and the International Energy Conservation Code (2015 IECC) also require continuous insulation in most applications.
- Use wider studs: For wood-framed construction, use 2×6 studs rather than traditional 2x4s to add more space for insulation between interior and exterior walls.
- Use spray foam: Use high-quality spray foam to insulate around wood-framed construction. This is a far superior method over less expensive insulation materials like batts and blankets.Â
- Control moisture: Since tightly sealed wood frame buildings are vulnerable to moisture accumulation in the water cavities, you’ll need to wrap your home’s exterior in a water-resistant and breathable material. Moisture can lead to wood rot and mold growth, which may risk a house’s structural integrity or harm your health.
- Use advanced house framing: Energy-efficient wood frame buildings use advanced house framing to minimize lumber use and waste.
- Use SIP panels: Structural insulated panels (SIPs) are made from a layer of foam insulation in between pieces of plywood, strand board, or cement. Using them can save you up to 50 percent in energy costs.
- Use EPS concrete wall insulation: To make an energy-efficient concrete structure, use wall systems with integral insulation made of expanded polystyrene insulation (EPS) or another insulating foam.
- Add an air and moisture barrier outside concrete: For concrete construction, add an air and moisture barrier to the exterior face of the concrete wall. Fully adhered membranes and fluid-applied air and moisture barriers work well with concrete construction.
Building Roofs for Energy Efficiency
An energy efficient roof (cool roof) is designed to reflect sunlight and absorb less heat than a standard roof. Cool roofs reduce energy bills, improve indoor comfort, and may extend the service life of the roof. Here are some tips to help you make one:
- Get your roof coated: Cool roof coatings have special reflective pigments or are white to reflect sunlight. A light-colored roof absorbs less than 50% of the solar energy, which reduces a roof’s temperature. Dark roofs, by contrast, absorb 90% of the solar energy.
- Use single-ply membranes for low slopes: For low-sloped roofs with a pitch of 9.5 degrees or less, choose single-ply membranes that are light-colored and reflect the sun.
- Use painted metal for low slopes: Painted metal roofs satisfy low-slope cool roof requirements for solar reflectance.
- Use shingles for steep slopes: Cool shingle roofs are overlapping panels made from wood, asphalt, metals, or polymers. Each shingle has a solar reflective granule coating that helps to keep the roof cool. They’re good candidates for steeper roofs.
- Use tiles for steep slopes: Tile roofs made from concrete, clay, or slate are another good option for steep roofs. Most tiles are naturally reflective, but treatments are available for tiles that are not naturally reflective.
- Build a green roof: Green roofs are perfect for usban buildings with flat or shallow-pit roofs. You can do anything with them, from making a basic plant cover surface or creating a working garden.
Energy-Efficient Glazing Systems
Your home’s glazing systems include its windows, skylights, and the glass portions of doors. Consider these tips to enhance window and door efficiency:
- Purchase energy efficient windows appropriate for your climate zone. Â
- Installing storm windows can lower energy bills by up to $350 a year.
- In the northern hemisphere, face major glazing areas south to take advantage of the solar heat gain in winter months when the sun is low. Â
- For warmer climates, limit south-facing glazing and install overhangs or other shading devices over the south-facing windows to prevent excessive heat gain during the summer.
- In the southern hemisphere, north-facing windows are best.Â
- Low-emissivity (low-e) window glazing helps to control solar heat loss and gains. In fact, computer simulations indicate that advanced window glazing reduces the space cooling requirements of new homes in warm climates by more than 40 percent.
- Choose energy-efficient skylights that have established minimum ENERGY STAR performance rating criteria by climate.
- New exterior doors typically fit and insulate better than old doors. When selecting a new door, consider buying the most energy-efficient door possible according to energy performance ratings associated with the local climate and the building’s design.Â
- If you plan to keep an existing exterior door, a storm door is a good investment.Â
- Caulking, weatherstripping, and the use of thermal window treatments or coverings can improve an existing window’s energy efficiency.
Ventilation in Energy-Efficient Homes
Proper ventilation is necessary for an energy-efficient home because air-sealing techniques may trap pollutants (like formaldehyde, volatile organic compounds, and radon). Ventilation also helps control moisture, which can cause mold growth and structural damage.
- Use an energy recovery ventilation system: Energy recovery ventilation systems provide controlled ventilation and minimize energy loss by transferring energy from conditioned air going out to fresh incoming air.
- Use localized exhaust fans: Fans above kitchen ranges and in bathrooms create spot ventilation, which removes indoor air pollution and moisture to increase the efficacy of a whole-house system.
- Combine natural and spot ventilation: While natural ventilation is the least expensive and most energy-efficient way to cool a home, it works best when combined with spot ventilation, ceiling fans, and window fans.
Energy-Efficient Heating and Cooling
Heating, cooling, and water heating account for the largest energy spending among homeowners. Here’s how to make your HVAC system more energy efficient to save money:
- Choose a high-efficiency system: The most efficient HVAC system is 95% efficient. That means 5% of the energy produced is expelled. Consider replacing your HVAC system every 10 years, but make sure any new ones are installed properly. Improperly installed HVAC systems can lower efficiency by up to 30%.
- Remove obstructions from the vents: Blocked vents require as much as 25 percent more energy to distribute air.
- Use a programmable thermostat: A smart thermostat helps you manage periods of time where the heating and cooling can be turned up and down.
- Change filters regularly: Dirty air filters slow air flow and make your HVAC system work harder. Clean filters also prevent dust from building up in the system, which can contribute to early failure.
- Get annual maintenance: Have your HVAC system professionally inspected at least once per year to protect its high efficiency and lifespan.
- Seal your ducts: Seal the ducts that move air to and from your HVAC unit—especially in your attic, crawlspaces, unheated basements, and garages. You can use mastic or metal-backed foil tape for the job. Then, wrap the ducts in insulation to keep them from getting cold in the winter and hot in the summer.
High-Efficiency Water Heaters
A water heater accounts for about 15 percent of a typical home’s energy use. You can find these energy-efficient water heaters that help you cut down on costs without compromising on comfort:
- Tankless water heaters: Tankless heaters only work when needed, so no energy is lost during standby operation.
- High-efficiency storage water heaters: Sometimes called “tank” water heaters, these use 10 to 50 percent less energy than standard models.
- Heat pump water heaters: Heat pump water heaters transfer energy from the surrounding air to water in a storage tank. They’re particularly ideal for warm climates with long cooling seasons.
- Solar water heaters: Solar water heaters use power from the sun to warm up your water. They can reduce operating costs by up to 90 percent.
Renewable Energy Sources
Incorporating renewable energy sources can significantly reduce a home’s reliance on the power grid. Generally, your options include grid-tied solar panels, small wind systems, hybrid wind and solar systems, or microhydropower systems on properties with flowing water.
Energy-Efficient Lighting
One of the easiest ways to improve your home’s energy efficiency is to switch to light-emitting diode (LED) bulbs. They’re energy-efficient, durable, and long-lasting, especially for task lights that consume far less than typical overhead fixtures.
You can also install controls such as timers and photocells that turn lights off when you’re not using them. If you’re used to lower light levels, dimmers can also help you save money and energy.
Energy-Efficient Appliances
ENERGY STAR-certified appliances use less energy and water than standard models and, therefore, cost less to use. Follow these tips as you outfit your new kitchen or laundry room:
- Get a top-mounted freezer: Refrigerators with top-mounted freezers use less energy than side-by-side or bottom-mount units.
- Find an electric ignition gas stove: Electric ignitions can lower your natural gas bill, since there’s no pilot light continuously burning.
- Check the flame color of your gas stove: Yellow flames mean that the gas isn’t burning efficiently.
- Clean burners and reflectors: Clean burners will reflect heat better and use less energy.
Energy-Efficient Landscaping
Believe it or not, your yard can factor into your home’s energy efficiency. Shady landscaping protects a home from direct light in the summer, as can planting trees along the southern and western sides. Once the trees lose their leaves, they’ll let more sunlight reach the building in the winter.