Smarter Living: Energy

Before you can start to make improvements at home, you have to take a cold, hard look at where you're wasting energy. This is no simple task -- unless you have infrared vision finding cold spots in your house can be hit or miss, leading you to seal your windows perhaps but leaving openings in your eaves that drain warm air straight out of your home. Your best choice is to invest the $300 to $500 it takes to get a certified home energy rater or auditor to check out your house. Hiring a certified rater may also make you eligible for government rebates if a program is passed. By implementing the audit's recommendations, you could easily trim your home's energy costs by 20 to 30 percent for annual savings of $500 or more.

What is the CO2 Smackdown? Read the overview.


1. Contact your utility to see if it provides free or subsidized energy audits.
Your utility may also recommend local raters, but be sure to follow the vetting process in step two.

2. Thoroughly research and select a certified energy rater
The Building Performance Institute and the Residential Energy Services Network are both professional bodies that certify home energy auditors. You may also check EPA's Energy Star listing.

Check references: Since the rater will become familiar with your home and some of your habits, it is crucial that you be able to trust them with this information. Get several references, contact all of them, ask if they were satisfied with the work done and get details from them on what the energy rater did and if they are saving energy as a result. Call the Better Business Bureau to ask about any complaints against the rater's company.

Ask prospective raters if they use a calibrated blower door. The blower door consists of a fan mounted in a frame that is placed in an exterior door. Calibrated blower doors include gauges that measure the amount of air pulled out of the house by the fan, giving the rater specific data against which to measure the effectiveness of any air-sealing work done by contractors later. If a rater doesn't use a calibrated blower door, find another instead -- for what you're paying, you should get quantitative data to measure from.

3. Prepare for the audit
List existing problems in your home, including condensation or other moisture problems.

Have copies of your energy bills or ask your utility to send a summary for the year.

Note the average thermostat setting for summer and winter

Pull out all the manuals or information you have on your appliances and heating and AC systems

Be prepared to answer the following questions:

  • Is anyone home during working hours?
  • How many people live here?
  • Is every room in use?

Prepare your house for the blower door test by:

  • Closing windows and opening interior doors
  • Turning down the thermostat on heater and water heaters
  • Covering ashes in wood stoves and fire places with damp newspaper
  • Shutting the fireplace damper, fireplace doors and wood stove air intake

4. The home energy audit (or rating)
On the day of the audit, accompany the rater through your home and ask questions.

During the audit, the home energy rater should:

  • Conduct a blower door test
  • Test your ducts for leakage
  • Test and tune up your heating and cooling equipment
  • Identify colds spots and the locations of air leaks

5. Results
A RESNET-certified rater will provide you with a HERS index of your home, a number ranging from zero to over 150, with the standard home hitting about 100 and a score of 0 representing zero net energy. The mortgage industry recognizes HERS ratings and they can be used to help you qualify for an energy improvement mortgage, which will finance energy efficiency upgrades to your home.

Just as important are the on-the-ground findings indicating where exactly your home is wasting energy and what can be done to improve the situation. For example, the rater will let you know if your ducts and insulation are correctly installed. Furthermore, raters can also determine if water and moisture are collecting in ducts, ceilings and walls, creating an environment for hazardous molds and causing damage that may not be visible until it becomes a significant cost to fix.

To see how much specific upgrades suggested by the audit might save you, fill out the Home Energy Saver questionnaire provided by the Lawrence Berkeley National Laboratory.


Some utilities will provide energy audits to their customers at reduced cost and offer discounts on the prices of CFLs.

For Federal tax incentives see the Tax Incentives Assistance Project for information about the limits on energy efficient home improvements. For a listing of state incentives, visit the Alliance to Save Energy.

Depending on your income, you may qualify for a free audit and other weatherization services through the Weatherization Assistance Program. This service is also available to renters.


If you live in an apartment, the U.S. Department of Energy provides an online guide to home energy audits with steps on how to conduct a DIY energy audit. You might also lobby your landlord to have an energy audit performed on your building and encourage him or her to take advantage of the energy efficiency tax incentives available now (see the Tax Incentives Assistance Project for listings) and in the future.

last revised 4/13/2011

Get Updates and Alerts

See the latest issue >

NRDC Gets Top Ratings from the Charity Watchdogs

Charity Navigator awards NRDC its 4-star top rating.
Worth magazine named NRDC one of America's 100 best charities.
NRDC meets the highest standards of the Wise Giving Alliance of the Better Business Bureau.

Donate now >

Share | |
Find NRDC on