Close Foam Insulation in Basement with No Sill Gasket
I am in the process of planning out finishing my basement. I am in zone 3A and my basement walls are hollow concrete blocks and the sill plate is non pressure treated wood that sits on top of the concrete block with no capillary break. The sill plate is in good condition but sits below grade on at least half of the basement and completely covers the cavities. The home sits on a sizeable hill with good drainage but it does have efflorescence towards the bottom of the wall all the way around the under ground portion of the wall but has never had a leak that caused any water.
I planned on cleaning the efflorescence off and using a sealer on the block walls then framing the walls 1 inch off of the block walls and then spray foaming the walls with closed cell foam. My concern is this will cause the moisture to move up and rot the sill plate. I do not want to jack up the home being that it is bolted down to add a capillary break.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part