GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Crawl space insulation and encapsulation

geoffpritchard | Posted in General Questions on

I’ve watched a number of videos and read articles regarding conditioning the crawl space.  One question that came up, do you insulate the walls first then apply the vapor barrier or should the vapor barrier be attached to the wall first and then insulation added over the surface of the poly?

IF one does close up the crawls space (encapsulate) is some sort of ventilation still required (like a low cfm fan) to help pull conditioned air from the house above?  I read 5 cfm/certain square footage of space for the fan.  What sort of venting would be required in the floor of the conditioned space?  Same as the fan?  More?  BTW — My location is in the Inland Pacific NW (Spokane WA area) if that helps.



I read J Lstiburek’s stuff as well as watching a video from NDSU Extension engineer.  Yikes.

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |