Programs for energy efficiency & conservationinclude:

Some Background: Air Leaks VS. Insulation

Sealing air leaks with caulk, spray foam, or weather stripping will have a great impact on reducing utility bills – even as much as 30%. Many homeowners automatically assume that insulation is the answer to reduce heating costs. But in most homes air leakage is the biggest robber of heating dollars.

Houses leak air because of the difference between indoor and outdoor air pressure. The biggest pressure differences are high and low in a building – in attics and basements. Warm air rises and leaks out any unsealed areas at the top of the building. Leaks inward tend to be at the bottom of the structure, pulling in cool air.

Many air leaks and drafts are easy to find because they are easy to feel – like those around windows and doors. But holes hidden in attics, basements, and crawlspaces are usually bigger problems. If you added all the small leaks together, it might amount to a hole as big as a football – that would be worth fixing.



Step One: Finding Air Leaks

A home energy assessment starts by finding air leaks.  Sometimes a blower door is used to both find and measure air leakage. The blower door test places a home under a known pressure and then measures how much airflow is required to maintain the pressure difference between indoors and outdoors. The tighter the house, the less air the blower door must move to maintain a given pressure. Besides measuring the airtightness of the house, it also helps to pinpoint specific air leaks.

Step Two: Fixing Air Leaks

The homeowner or contractor seals the identified leaks with materials that include foam, acrylic adhesive tape commonly used to tape air barriers, acoustical sealant, polyurethane caulk, polyethylene sheet, and rigid foam.

Typical attic culprits include kneewalls, the attic access, soffits, bulkheads and dropped ceilings, chimneys and plumbing vent stacks.

Basement culprits are rim joists and utility penetrations, including dryer vents and utility pipes.

Step Three: Verifying the Fix

The final phase is verification. After leaks are sealed, a blower door test can be repeated to measure improvement on the airtightness of the home.

Homeowners are often concerned about sealing their house too tightly as a certain amount of fresh air is needed for good indoor air quality; however, this is very unlikely in most older homes.  After any home sealing project, have a heating and cooling technician check to make sure that your furnace, water heater, and dryer are venting properly.