not really a garage question but

[notme_76]

i'm wondering about whats the best way to insualate the header area of an old house,(between the floor joists) where hte slab joins to the house..someone had fibreglass bats in there but the back of htem was all black from moisture over the years im guessing?, there has to be a better system? the area never gets wet so it has to be moisture seeping thru it from the inside, there was no vapour barier over that area of insualtion and it would be pretty damn hard to get a good seal over it
what would be the best way?

 

[Boyd Who]

I have a similar issue with our 100 y/o house. The stone foundation walls are 18" thick and there is a space between the first and second joists that have no insulation. The floor around the perimeter of the main floor is always cold in the winter. I'm hoping to get some expanding foam insulation blown in later this year, but I have to check with a couple of places about it first.

 

[walrus]

i'm wondering about whats the best way to insualate the header area of an old house,(between the floor joists) where hte slab joins to the house..someone had fibreglass bats in there but the back of htem was all black from moisture over the years im guessing?, there has to be a better system? the area never gets wet so it has to be moisture seeping thru it from the inside, there was no vapour barier over that area of insualtion and it would be pretty damn hard to get a good seal over it
what would be the best way?

Closed cell foam, not sure where you are located but if its in a cold area, the moisture could be condensation from warm moist indoor air hitting the cold joist area, going thru dew point

 

[Stuart in MN]

You can use rigid foam as well. Cut rectangles to fit in each joist bay and then use a can of spray foam to seal around the edges. Leave the rectangles a little loose around the edges, so you can get the spray foam to fill in all the way around.