Home Energy Audits

June 13, 2007

I had the chance to learn more about evaluating home energy efficiency at a seminar about energy rating for homes. This is particulary valuable here in the State of Michigan because Michigan is in the bottom 5 states for energy efficiency in home construction. According to the EPA, only Hawaii is worse than Michigan. There is new legislation being introduced in the state to address some of these issues (which I will be writing about shortly), but, at present, the state requirements are very lax, and saying that a house meets the building code for energy doesn’t mean all that much.

Production homebuilders would rather save a few hundred dollars so that they can keep their costs low and sell homes at the lowest price they can. They are unconcerned about the operating cost of the home, and many homebuyers are following them and only asking about the seling price. The cost of this negligence arrives in high energy bills for these homes, which buyers must deal with year after year.

But, there are some federal incentives that encourage the building of more efficient homes. The Energy Policy Act of 2005 includes a $2000 credit (not just a deduction) for home builders for the construction of a home that meets energy efficiency targets. (The deadline on the Energy Act is presently January 1, 2008, but it is expected to be extended by Congress very shortly.) “Home builders are eligible for a $2,000 tax credit for a new energy efficient home that achieves 50 percent energy savings for heating and cooling over the 2004 International Energy Conservation Code (IECC) and supplements. At least 1/5 of the energy savings must come from building envelope improvements.” — (EnergyStar link)

In order to obtain this credit, the house must be rated by a Home Energy Rater, who performs tests to verify the construction meeting the higher standards. Home energy audit costs vary from provider to provider, but are usually on the order of a few hundred dollars. This usually includes a “blower door test” where the house is de-pressurized with a large fan set in the front door. The pressure differential helps to evaluate the extent of air leaks in the house.

A Home Energy Rater is a specialized contractor who performs a standardized evaluation of the energy efficiency of your home. The evaluation includes:

* on-site inspection
* air leakage test of your home and duct work
* computer analysis
* estimated savings
* home energy rating
* Home Energy Raters typically perform the role of an independent consultant, but some will offer to make improvements. — (EnergyStar link)

In many cases, it is extremely important to look at these things when the home is being constructed. Many things that contribute significantly to the performance of the house need to be properly incorporated at the time of construction. It is usually extremely difficult to try to go back later to fix things, often it is prohibitively so. Many of these things are, in the words of our speaker, “things you have one shot at to do it right.” Once walls are closed in and systems are concealed behind drywall, it is very expensive to go back to try to fix those things.

Adding a renewable energy system can be flashy and can show your dedication to a green lifestyle. However, taking care of the efficiency of the building first will mean that you will get more enjoyment out of the renewable system you put in place. You will need less supplemental power supplied from other sources. Increasing efficiency and building homes the right way in the first place is the best step to take for energy savings.