Do I have to worry about building my house too tight?
In an extremely tight home, the air inside your home becomes stale and unhealthy. But in most homes, there’s a fair amount of ventilation, however it’s usually due to outside air entering and conditioned air leaving your house uncontrollably through cracks and openings. Based on air temperature and air pressure, you can lose conditioned air and experience drafts throughout the year.
But my home doesn’t really leak enough to cause a problem, does it? According to EnergyStar, air leakage accounts for 25-40% of the energy used for heating and cooling a typical home. Surprisingly, this energy inefficiency is equivalent of having a window open, year around in your home. That’s not just letting air in, but it’s also letting moisture in to your home.
Our advice to customers is to build your home tight and then ventilate it right. Using good windows, doors and spray foam insulation creates a tight building envelop, which gives your HVAC system complete control over the air inside. This helps it operate more efficiently and effectively, which saves you money.
But you should also work with your insulation contractor and your HVAC contractor to correctly size your HVAC system to accommodate a home insulated with spray foam. This will keep your unit from short cycling, which is not only inefficient but more importantly, it prevents your unit from running enough to remove the excess humidity from the home. Request that a Manual J specifying a tight building envelope be completed, and the unit be selected based on the results, not just a rule of thumb suggestion.
Then, be sure to add mechanical ventilation to your HVAC system. This will provide the amount of ventilation required for healthy living but not enough to tax the heating or cooling functions.
Companies: Rhino Linings