Can I Over-Seal My House, or Make it Too Tight?

A contractor blows insulation into an attic.By Energy Star and Thomas Elzinga

While it is possible to seal a house too tightly, it is unlikely in most older homes. A certain amount of fresh air is needed for good indoor air quality and there are specifications that set the minimum amount of fresh air needed for a house. You want to seal tight, and if necessary, ventilate right.

How much air that moves through your home is measured in Air Changes per Hour, or ACH. For older homes prior to 1993 achieving an ACH of 5 is a good goal. An ACH from 6-9 is moderately leaky and greater than 9 is very leaky.

If you are concerned about how tight your home is, hire an air sealing company to perform air leakage tests using diagnostic tools and make sure all combustion appliances are operating properly. If your home is too tight, the air sealing company may recommend that a fresh air ventilation system be added to your HVAC system. If you have your whole home professionally air sealed you can qualify for a CEC rebate. Please contact us for more information.

For additional information on air sealing you can visit the Energy Star website for some great DIY tips and tools that you might need.