Conduct a Home Energy Assessment

Home Energy Assessment: A Few Notes on Safety

As you conduct your home energy assessment and begin making improvements to your home, you may come across ducts or pipes that look as if they are insulated with asbestos. If you suspect your home contains asbestos, do not touch it. Call a professional who can assess the situation and remove the asbestos safely.

When sealing air leaks in your home, be aware of the possible danger that can occur when combustion (non-electric) appliances and exhaust fans compete for air. This may result in too much carbon monoxide in your home. A working carbon monoxide detector is advisable. Though air pollution and back drafts are unlikely, especially in older homes, consult a certified professional if you’re uncertain. In general, understand your knowledge level and your limitations. If you see something that looks concerning, consult a professional.

Getting Ready

Before you begin your do-it-yourself home energy assessment, create or print off a checklist of areas you want to inspect (see a sample checklist below). You should also keep track of the areas of your home that need improvement, either by writing down what you’ve found, or by using colored tape to indicate what rooms and features need energy efficient upgrades.

Here are some materials you’ll need before you begin:

  • Dust mask, eye protection and gloves
  • Pen or pencil and your checklist (below)
  • Calculator and tape measure
  • Screwdrivers
  • Incense stick or candle
  • Flashlight
  • Ladder
  • Painters tape to mark problem areas

You may also want to consider making some of the easier fixes on the day of your home energy assessment. If you’re planning to do so, you may want to pick up some low cost materials to address common problems. Suggested materials include:

  • Caulk
  • Weather stripping
  • Insulation
  • Plastic sheeting for single-pane windows
  • Compact fluorescent light bulbs and/or LED (light-emitting diode) bulbs
  • Duct sealant (mastic)
  • Carbon monoxide detector

Detecting Air Leaks

Air leaks around doors, windows and other areas can cause significant energy loss and make your home less comfortable. Try one or all of the ideas below to detect air leaks. You may also want to consider hiring a professional to help you identify and fix other sources of air loss in your home.

1.       Visually inspect areas around your home that are most likely to have cracks or gaps which could cause air leaks, including windows, doors, etc. Use the checklist below for guidance.

2.       Depressurize your home and conduct a “smoke test.” This test works best on a day that is cool and windy.

  1. Turn off your furnace.
  2. Shut all windows and doors.
  3. Turn on all of your exhaust fans, such as those in the kitchen or bathroom, that blow air outside.
  4. Once your home is depressurized, light an incense stick and pass it around doorways, window frames and other areas of common leak sites (see above). If smoke is sucked out of a room or blown into the room, it means you have a draft.

3.       Close and lock your doors and windows on a plain sheet of paper. If you can pull the paper out without it tearing, it means you have an air leak. You can also use the paper technique with your refrigerator door.

4.       At night, walk around the inside of your house and shine a flashlight on areas prone to air leaks like windows, doors, foundations and vents. Have a partner stand outside to observe. If there are large cracks or gaps, your partner will see a ray of light. Unfortunately this test does not work well on small cracks, but can be a helpful start for finding or ruling out larger issues to repair first.

Checking Insulation Levels

Insulation helps keep the energy you purchase inside of your house where it belongs. By checking to ensure insulation in your home meets recommended levels and installing additional insulation where needed, you can save a large amount of energy.


  • Check to see if that the attic hatch is weatherstripped and closed tightly
  • Determine if openings for pipe, ductwork and chimneys are sealed
  • Look for a vapor barrier under the attic insulation (usually made of tarpaper, Kraft paper attached to fiberglass batts or a plastic sheet). The vapor barrier prevents water vapor from reducing the effectiveness of the insulation and can prevent mold.
  • Inspect attic vents to make sure they are not covered by insulation. Check the insulation level on your attic floor with a ruler. If you can easily see your joists, you should add more insulation. If your attic insulation covers your joists and is distributed evenly, you likely have enough insulation. In Virginia, new homes and additions require 10-12 inches of insulation. Find out more (PDF).


  • Follow all Department of Energy safety precautions.
  • Turn off the circuit breaker or unscrew the fuse for any outlets in the wall.
  • Use a lamp or radio to make sure outlets are no longer conducting electricity. 
  • Remove the cover plate from one of the outlets.
  • Using a non-metal, thin, long stick (i.e., chopstick, wooden skewer), gently probe into the wall. If you encounter slight resistance, you have insulation there.
  • Note that this method cannot tell you if the entire wall is insulated, or if the insulation has settled. You may want to hire a professional to conduct a thermographic inspection.

Inspecting Heating and Cooling Equipment

Most heating and cooling equipment should be inspected at least once per year or as recommended by the manufacturer. While inspecting your equipment, look at the ductwork to make sure there aren’t any dirty streaks, which indicate air leaks. This can also be an opportunity to tape joints or paint on duct sealer to prevent leaks.

You should also make sure that your water heater tank isn’t emitting heat. Here’s a quick test to tell if your water heater tank is well-insulated: touch it carefully. If the tank is warm to the touch, it could use additional insulation.

Sample Checklist 


What To Look For

How To Fix



Insufficient insulation; holes in the ceiling and floor; weatherstripping around hatch

Install additional insulation; use spray foam and caulk for holes


Basement and crawl spaces

Insufficient insulation; gaps in flooring

Install additional insulation; use spray foam and caulk for holes


Exterior walls

Insufficient insulation

Install additional insulation; use spray foam and caulk for holes


Electrical outlets and switch plates

Cracks; air leakage

Install foam or rubber gaskets; install child-proof plugs


Overhead lighting and lamps

Inefficient light bulbs; air leakage (esp. for recessed lights)

Replace bulbs with CFLs; replace recessed lights with Air Loc models



Air leaks; cracks in walls

Seal gaps with spray foam



Air leaks and drafts

Weatherstripping; caulk; storm windows; install energy-efficient window



Cracks or holes




Cracks or holes

Weatherstripping; install or replace door threshold and door sweep



Check flue; cracks and holes

Close flue; install fire-rated sealant


Air-conditioning units

Old or dirty air filters; cracks and air leaks

Replace or clean filter; caulking; duct mastic


Air registers

Dirty registers; disconnected ducts; air leaks

Clean air registers; replace duct work; reattach duct connections


Plumbing, pipes

Cracks or holes around plumbing

Seal gaps with spray foam



Cracks or holes

Install insulation; cement patches



Cracks or other gaps

Caulk; install insulation


Mail slots





Gaskets and seals

Replace gasket and seals; consider newer model


Water heater and piping

Insufficient insulation

Install insulation jacket and sleeves


Water heater thermostat

Set higher than 120 degrees

Set to 120 degrees


Electronics, small appliances

Plugged in all of the time

Install power strip and turn off when not in use



Insufficient insulation

Install insulation



Insufficient insulation

Install insulation


Exhaust fans

Large gaps where fan meets wall

Seal gaps with spray foam


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