Why You Should Get an Energy Audit

In an era of cheap energy, people who lived in very old houses could concentrate on making cosmetic and structural repairs. Lord knows, that could be overwhelming enough. If the boiler went through several thousand gallons of fuel oil in a winter, well, there were worse things.

But we are rapidly leaving the era of cheap energy. In the summer of 2008, as the price of crude hit an all-time high of $147 a barrel, the price of No. 2 fuel oil reached $4.70 a gallon in the Northeast. The price didn't stay there long, and today is about $3 a gallon.

Still, that is not cheap and prices will rise again.

Unless someone has undertaken a serious energy retrofit, the cost of heating an older home is becoming an increasingly heavy burden, easily enough to make selling and moving an attractive option. An exaggeration? Someone I know with a big 19th century farmhouse told me he has spent $8,000 a year for heat. Not every budget can handle that expense.

We've learned to build houses that use far less energy than that. Some are even net-zero energy homes, which produce as much energy from wind or photovoltaic sources as they consume in a year. But houses like that take meticulous planning and extraordinary attention to detail during construction, along with materials that simply weren't available even 50 years ago.

Techniques that make high energy efficiency possible are best built into a house from the start. Walls in a super-efficient house are often insulated to R-40, roofs to R-60 or higher. Every potential air leak has been sealed; windows are double- or even triple-glazed.

Some of these features can be adapted to old buildings. But where to begin? High-performance windows can easily top $1,000 each, not including the labor to install them and the extra work to preserve or recreate period trim. Re-insulating outside walls can be disruptive as well as expensive.

On the other hand, sealing air leaks around a chimney chase or at wiring and plumbing penetrations might take a morning's work and $50 in materials.

Which pays the most dividends? Most of us don't have the expertise to know.

The right place to start is with an energy audit, a top-to-bottom look at your house by a trained professional who can then make suggestions on which upgrades can do the most good. Inspectors have access to sophisticated tools that help pinpoint the sources of energy loss, including calibrated blower doors that measure how tight the building is and infrared photography that identifies specific areas of heat loss. Everything from windows to heating appliances and air ducts should be on the list.

A thorough energy audit isn't cheap, but it's a lot more than informative than an off-the-cuff opinion. Savings can be significant and just as important, you'll have a real plan. You can read more about energy audits at the U.S. Department of Energy's website. Go to www.energysavers.gov/your_home/energy_audits.

To find an auditor, you could start with the state or local office that deals with weatherization programs or with your local gas or electric utility. Because these techniques are so intertwined with energy efficient construction, you might also check with a local green-building association. However you find an auditor, show the same care you'd use in choosing any professional.

If would be well worth your time.