DIY Life

Do you need an energy audit? If your electricity and gas bills are higher than they should be, or if you have an older home, you probably do. You already know about insulation, radiant barrier, efficient windows, and Energy Star appliances.

The problem, of course, is that these are many areas to address, but you don't have pockets that deep. Things need to be prioritized here. And that's where the energy auditor comes to the rescue. After his inspection, he'll provide you with a report that tells you:

• Where you stand with your current cooling and heating system.
• Your home's efficiency overview. This details where your home is bleeding hot and cold air.
• The most efficient use of your dollars to save you money by saving energy.
• Bigger outlays of cash that will begin paying for themselves right away.
  

After the break, I'll describe how the tests are done, and the costs involved.

How much will the audit cost? Typically, between $250 - $400, depending on the size and complexity of your home. The good news is that you may be able to score a rebate from your local utility companies.

Checking the heating system and the hot water heater

The heating system is a huge energy sink, especially for folks that live in colder regions. What the auditor is concerned with here is the combustion efficiency of the furnace. He gets a reading by drilling a small hole in the flue into which he inserts the wand of an electrical gas analyzer.

In addition to the combustion efficiency, this test also yields data on the furnace draft pressure (if it's too high, gases could leak back into the home) and a carbon monoxide concentration.

If your home has a gas-burning hot water heater, the auditor should conduct a backdraft test. This test is conducted by holding an open flame by the flue on top of the heater. If it's operating properly, the flame should be drawn up into the flue.

The air infiltration rate test

The rate at which your home "leaks" air has a huge impact on your energy bills. If doesn't matter how efficient your heater and air conditioner are if your home has the swiss cheese syndrome. Most auditors call this test a "blower door test" because that's what it involves.

The auditor first closes your windows and doors except for one door. At this doorway he places a fan and seals the entryway with sheet plastic. Once he turns the fan on, air flows out of the home, reducing the internal air pressure.

If your home is newer, it's probably tighter than the average since this is what the building trends have been. But on older homes, you can expect to save as much as twenty percent on your energy bills. Who wouldn't go for some of that?

But how does he find those leaks, you ask?

The fan is calibrated so that the auditor can note the speed of the fan blade needed to maintain an even pressure difference between indoors and out. He then looks for suspect areas that need to be sealed better.

The auditor uses thermography with an infrared scanner. This is really pretty cool technology. I first saw it in action when I worked for a Marriott hotel. There, we brought in an analyst during the energy audit. He would take infrared photos of electrical components to determine which ones were likely to fail. The "redder" the picture showed up, the hotter it was, and therefore closer to failure.

During a home audit, the auditor looks for these color differences to determine where the home is letting outside air in. Very clever.

Your report card provides the scoop

With the final report in hand, it's easy for you to prioritize the DIY projects that will help you keep more of your money. It should indicated the good/bad areas and how much you will save on each repair. It may recommend things such as:

• If you need to insulate ductwork or your water heater.
• Where you can use motion sensors to turn off lights.
• If your shower heads should be modernized (think low-flow).
• Where to seal around windows and doors.
• Which appliances should be upgraded to Energy Star rated ones.
  

Check with your energy companies to determine where you can get rebates. Look at any recent tax rules that may give you a break. And keep that report card to use as your checklist.