# Basement wall insulation



## Windows on Wash (Aug 30, 2011)

It would be best to insulate the space.

Any type of batt insulation is fine in this case to the proper depth.

Batts are not great on the walls by themselves but if you are referring to overtop of the foam, again, anything works.

Make sure they are unfaced.


----------



## Gary in WA (Mar 11, 2009)

The batts should really be directly touching the foamboard to eliminate any conductive loops; http://joneakes.com/jons-fixit-database/743

As per code, the frame wall/cavity behind should be fire-stopped every 10' horizontally; http://publicecodes.citation.com/icod/irc/2006f2/icod_irc_2006f2_6_sec002_par018.htm

ADA the drywall, to stop room air from getting to the concrete wall; http://www.buildingscience.com/documents/information-sheets/air-barriers-airtight-drywall-approach/

Remember the rim joists; http://www.buildingscience.com/docu...joist/files/bscinfo_408_critical_seal_rev.pdf

For your location; if near Boston- 1" f.b. leaves the inside f.b. at 39* on your coldest days in winter with* only 32% RH *in the room. 1-1/2" f.b. = 57%RH at 70*, much safer against condensation there. If near Worcester- *1" f.b. = 24%RH*, 1-1/2" f.b. = 49%RH.

Gary
PS. welcome to the forums!


----------

