When warm humid air enters crawl space vents, where is the first place it will give up its moisture? On the coldest surfaces, right? The coldest surface is likely to be your ducts when the air conditioning is on. Water is a conductor, not an insulator. So when a duct is wet, it is warmed by the summer air (humidity) that came through the crawl space vents.
A home with a dirt crawl space costs more to heat and cool. If your crawl space is vented, those vents make your floors cold upstairs. This is not only uncomfortable but makes your energy bill rise during the winter and summer months.
Damp air uses more energy to heat and cool and costs more money. Damp air puts a latent (hidden) load on the HVAC system. Everyone knows they need to run their AC on a hot, humid day. But what about humidity from inside the building? Same thing. If you get rid of humidity from your crawl space, you save money on heating and cooling costs.
How much money? You will save 15% to 25%. That’s a lot of money! Over the years, it really adds up. You are paying the price every month in higher energy bills by living in a house with a dirt crawl space. Of course, there are variables–such as how many foundation vents you have, whether you live in a one-or-two- story home if you have ducts in the crawl space, how big your crawl space is, etc. Fixing your crawl space is one home repair you can’t afford to make.