UNITY - A course offered next month at Unity College will train a new set of experts who will learn - quite literally - how to take your home’s temperature.

The environmental college, at the urging of the state’s MaineHousing office, has created a three-week course that will lead to certifying a new batch of home energy auditors, who can either hang out a shingle and help homeowners find where their energy dollar is going, or apply what they’ve learned to house construction or related fields.

"It’s geared primarily to contractors and those in the building trades," said Mick Womersley, Unity College’s interim provost and an instructor with a special interest in and knowledge of sustainability and energy efficiency.

Womersley built a straw hay bale house several years ago, and now is renovating an old farmhouse.

The state wants to see more certified home energy auditors to work at evaluating homes for state and federally funded upgrades designed to help low-income people get the most bang for their shrinking energy dollar.

"There just aren’t enough of them in the state," Womersley said.

Unity College adjunct professor George Callas, who is a certified home energy auditor, estimates there are about 200 people in Maine with the certification. But less than 50 are active, he said, and many of those work for community action programs and other non-profits.

At its most basic, a home energy audit might begin with the auditor placing a fabric curtain in the house’s outside door frame. A high-power fan fitted into the fabric then sucks all the air out of the house, and the technician walks around with a smoker device looking for outside air incursions.

The blower door test also provides data about the temperature of the air passing through the device as it leaves the house, from which more information about the house can be drawn. Other tests measure electric use, the effect of sunshine on a house, and other energy considerations.

The course will cover construction standards, codes, appliances, installation of heating plants, and the latest approaches to tightening up a house.

"There’s some basic physics involved," Womersley said, as well as some math.

Callas said building contractors would do well to take the course, even if they don’t plan on taking the certification test. He estimates that 80 percent to 90 percent of homes built in Maine do not use the current best practices when it comes to energy savings.

Womersley said Maine’s older housing stock is notoriously poorly insulated. But an energy audit is also appropriate for new construction, and ideally should be conducted just before a new house is insulated, to learn which parts of the building envelope are vulnerable to air incursion.

"The average Maine house is very poorly insulated," he said, and the energy audit helps the homeowner decide which fixes to take on, based on return on investment.

"I’m thinking of taking the course myself," Womersley said.

The class will be taught by Callas and Tony Gill. Callas agreed the information gleaned in home energy audits should affect construction.

"This is really about changing the way we approach our houses, the way we build them, the way we retrofit them. It’s a whole new game," he said.

The class will be offered from 8 a.m. to noon, Monday to Friday, beginning May 14. The cost for non-Unity College students is $550. Passing the course makes one eligible to take the state certification exam.

For information, call 948-3131.