How To Conduct a Basic Home Energy Audit
An energy audit does not have to be difficult or intimidating. A simple review of the home can identify numerous areas that, if improved, will lead to efficient operations. The following audit outline deals with no cost or low cost ways to improve your energy efficiency.
Two Important Facts
There are two energy facts that should be your guide for improving your comfort and efficiency.
Heat moves from the warm side of a barrier to the cold side. This means that your home loses heat in the winter and gains it in the summer. The goal is to block this heat movement if you can.
All materials resist the movement of heat to some extent. The higher the Resistance to heat movement, the higher the R-value. We try to build into our homes the highest R-value we can. This is where insulation can help.
Air infiltration can be a home’s biggest energy waster. All of the holes, gaps, and cracks in a home’s walls, ceiling and foundation are areas where there is no resistance to heat movement. The goal is to plug as many of these leaks as you can.
If you added up all of the holes, gaps and cracks in the average American home they would add up to the area of one standard window. If not plugged, it would be the equivalent of leaving a window open year round.
1. SIDE WALL INSULATION
- The first question to ask is, "Do you know if you have side wall insulation?" If you do, there is nothing to do here. Move on to the next item.
- If you do not have wall insulation and you are interested in adding some, contact a professional insulation installer (you can find them in the Yellow Pages under insulation), for an estimate.
- Remember, if you have a choice between attic or wall insulation, insulate your attic. You get more savings.
- Walls without insulation can be insulated in various ways. Possibly, the simplest is to drill holes in the home’s siding, and blow insulation through the holes into the wall space. A plug is placed into the hole to prevent weather infiltration.
- If you don’t know if your walls are insulated you may be able to find out by trying a simple test. Take off an exterior wall switch plate (either plug or light switch). If there is a small gap between the electrical wiring box and the wall, look to see if insulation is visible.
2. EXTERIOR SWITCH PLATES
- While you are evaluating your exterior walls for insulation, you can check for switch plate insulation. Air can leak into and out of a home though switch boxes (plugs, light switches) in your home’s outer walls. Switch boxes usually don’t seal well. Placing a foam gasket behind the switch cover can help plug this leak. These gaskets may be purchased at a hardware or lumber store.
3. ATTIC INSULATION
- The first question to ask is, "Do you know if you have attic insulation?" If you do, the next question is, "How much is there?" If you have attic insulation, and it is 12" – 14" deep, there is nothing to do here. Move on to the next item.
- If you do not have attic insulation, or the depth is 6" – 8" or less, and you are interested in adding some, contact a professional insulation installer (you can find them in the Yellow Pages under insulation), for an estimate. Remember, if you have a choice between attic or wall insulation, insulate your attic. You get more savings.
- Attics can be insulated in various ways, and with various materials. Some common types of insulation are fiberglass rolls (batts), fiberglass loose fill and cellulose loose fill.
- Some insulation materials, like cellulose, can be dumped into an attic, but more commonly is applied with a blower machine. Blower machines may be rented, however, if you are not comfortable with performing this on your own, contact an insulation professional
- If you don’t know if your attic is insulated, try to find your access door and check. Use a ruler to measure the depth. If you don’t know where your access door is located, or don’t have one, contact an insulation professional to check for you.
- Remember to insulate and weather-strip your attic access door.
- Windows can be a large energy waster. You want to ensure that you’re getting the best performance out of what you have. Because glass has a very low resistance to heat movement, your goal here is to reduce air infiltration. You also want to take advantage of shading at the appropriate times.
- Make sure the window seals well. If the window is loose in its track, install some weather stripping to tighten it up.
- If you have cracked or missing panes, have them replaced.
- If you have storms, use them during heating and cooling season.
- If you notice cracks between the wall and window molding, apply caulk to plug this leak.
- If you have shades, open them on sunny winter days to gain solar heat. Close them on hot sunny days to reduce solar heat gain.
- During cold winter weather, use clear plastic window wraps to stop air infiltration.
- If you are interested in replacing your windows, contact a professional contractor for an estimate.
- There are some efficient windows out there. Generally, you want to look for a double pane, argon gas filled window with a low emittance (low E) rating.
- Doors can also be a large energy waster. Some door materials have a low resistance to heat movement. Foam filled steel doors are very efficient. However, hollow wood doors are not. You want to ensure that you’re getting the best performance out of what you have. Your goal here is to reduce air infiltration.
- Make sure the door seals well. If the door is loose or warped so you can see daylight around it when it is closed, install some weather stripping to tighten it up.
- Make sure the threshold seals the bottom of the door. Again, if you can see daylight under the door when it is closed, replace the threshold.
- If you have a storm door, use it during heating and cooling season.
- If you notice cracks between the wall and window molding, apply caulk to plug this leak.
- If you are interested in replacing your doors, contact a professional contractor for an estimate. There are some efficient doors out there. Generally, you want to look for solid core door, or one that has insulation inside. Steel doors with magnetic closing are a good choice.
- A fireplace provides a large opening for heat to transfer in and out of a home. Fireplaces can have a negative efficiency. This means that they can take more heat out of a home than they provide. Your goal here is to stop air infiltration.
- Make sure the flue damper closes and seals tightly.
- Keep the damper closed when not using the fireplace.
- Install a tight sealing set of glass doors to stop air movement.
- If you have a wood-burning fireplace, you may consider installing a sealed gas-burning fireplace. These systems are much more efficient. Contact a professional installer for more information.
- If you don’t use a fireplace, consider adding board insulation to resist more heat transfer. Make sure the insulation is removed before any fire is built.
- Remember that when a fireplace is in use, even though you may feel warm while near it your furnace can be running more to replace the heat that is being drawn up and out of the home.
7. THERMOSTAT SETTING
- Where you set your thermostat setting is a comfort issue. Some of us know that we can save money if we set our thermostat lower in the winter and higher in the summer. Some are willing to pay the higher prices to remain comfortable. Our goal here is to remember that there may be other lower cost ways to keep warm or cool.
- Turn your thermostat down 5 – 10 degrees in winter when you go to bed at night and use an extra blanket if you need one. Your furnace will have to catch up in the morning, but you will save more than the catch up will cost.
- Turn your thermostat down 5 – 10 degrees in winter when you are not at home. Your furnace will have to catch up when you get home, but you will save more than the catch up will cost.
- During cold weather, while home and before going to bed, turn your thermostat down 5 degrees and dress warmer, or use a blanket or comforter.
- Consider installing a programmable thermostat that will make changes in temperature settings automatically. Contact a heating and air conditioning professional for more information.
- Turn your thermostat up 5 – 10 degrees in summer when you are not at home. Your air conditioner will have to catch up when you get home, but you will save more than the catch up will cost.
- Turn your thermostat up 5 – 10 degrees in summer when you are home and use fans to remain cool. Fans use much less energy than your air conditioner.
- During hot, humid weather, try running your air conditioner in the morning for a short time (20 minutes) to clear the home of humidity. This may cause you to run your air conditioner less during the day.
8. WATER HEATER & WATER TEMPERATURE
- A water heater heats and holds water. As heat moves out of the tank, the water is heated to match the thermostat setting. Your goal here is to keep as much heat in the tank as possible.
- Newer water heaters have adequate insulation built into them. Older water heaters may benefit from the installation of a water heater insulation jacket. You may also save by installing the first 6 feet of water pipe insulation. These products may be purchased at a hardware or lumber store.
- Water temperature is another comfort issue. We may know that we can save money if we turn our water heater temperature down, but we want hot water. You can check your water temperature with a candy thermometer.
- Reduce your water heater temperature.
- Install a water heater insulation jacket.
- Install 6 feet of hot water pipe insulation.
9. RIM JOIST INSULATION
- A clean furnace filter helps your furnace and air conditioner run more efficiently. A dirty filter makes your system work harder to move warm and cool air around your home.
- Replace dirty furnace filters with clean ones on a regular basis. Every 2-3 months may be appropriate unless the weather is very hot or very cold. Then every month may be necessary. This should be done year round.
11. CRAWL SPACE / FLOORS
- If your home does not have a basement, it may have a crawl space under the floors. The floor is not a good insulator. Warm air will move in and out of the room through the floor into the unconditioned space below. There are two goals here, stop any air infiltration through the floor and corners, and raise the resistance to heat movement with insulation.
- If your home has living space above a garage, or a portion of the home is extended over mid-air, the floors here will loose energy if they are not insulated and the holes plugged.
- The first question to ask is, "Do you know if you have a crawl space, or unconditioned space below a floor ?" If you do, ask the next question, "Is the floor insulated?" If you have floor insulation, and it is at least 6" deep, there is nothing to do here. Move on to the next item.
- If you have a crawl space or a floor over an unconditioned space and do not have floor insulation, and you are interested in adding some, contact a professional insulation installer (you can find them in the Yellow Pages under insulation), for an estimate.
- Because the insulation must be attached to the underside of the floor, fiberglass roll insulation is usually used.
- If you don’t know if you have a floor over an unconditioned space or if it’s insulated, try to find your access door and check. The access door may be on the outside of the home. If you don’t know where your access door is located, or don’t have one, contact an insulation professional to check for you.
- Remember to insulate and weather-strip your crawl space access door.
12. DUCTS IN UNCONDITIONED SPACES
- If your home has furnace or air conditioner ducting that runs through unconditioned spaces (areas not heated or cooled), you may be reducing the efficiency of your system. Ductwork does not resist heat movement well.
- Warm or cool air is created by your furnace or air conditioner and then blown to parts of your home. If the ducts that carry this conditioned air moves through an unconditioned space, it can loose or gain heat (depending on the season). Your furnace or air conditioner must work harder to satisfy your thermostat. Special duct insulation may be purchased at a hardware or lumber store.
- Likewise, if the ductwork has cracks or gaps in it, it will loose air. There are two goals here, improve the resistance to heat movement in the ducts, and reduce air movement out of the ductwork. Duct taping the joints and corners of your ductwork can reduce air losses.
- Insulate your ductwork that moves through unconditioned space.
- Duct tape all cracks and gaps in your ductwork.