Q – What should I do to keep humidity out of my crawlspace without spending a fortune?  I know it can be an issue but I don't have much money to spend.

I know you answer this a lot, but I guess I haven’t been paying attention, and I think it’s going to be a humid summer.  Please, please, please help me.  I promise I will listen.

Samantha in Locust Grove


A – Ok – pay attention.  I am only going to answer this now (again) because:

A) – I don’t think enough people do this

2) – it’s pretty important, and

D) – it’s getting to be prime humidity season.

Here are the basic things (i.e. least expensive and the minimum) things you can do.

  • Go to your favorite hardware store and pick up some 6 mil plastic.  Spread the plastic over the ground in your entire crawlspace, lapping it up the walls just a bit.  Overlap the seams – covering the ground the best you can.  6 mil is the minimum requirement by code.
  • Get some batt-type R-13 insulation and roll it up into your floor joists.  Put the paper side up.
  • Close or seal your crawlspace vents.

Now you’ve done all you can on a limited budget. 

If you want to spend some money, and get even better results, you can get your whole crawlspace encapsulated, thicker plastic, wall coverings, better sealing of openings and a quality dehumidifier.  That is the best you can do.  Check out my website for companies that do this very well.

Remember the stack effect on your house.  Think of it as a big chimney.  Air comes in from the bottom and goes out through the top (attic).  So you want to have less moist (humid) air entering your home from the crawl, so the better you can get your crawlspace encapsulated the better off your whole house will be.