Insulating beneath an addition: how would you do it?
We purchased our home a couple of 12 months in the past and knew there was some stuff that wanted work. Off the again of the home an addition was constructed. The home is on a hill so the realm beneath the addition is definitely open to the air (you may stroll out to beneath the addition from the basement). We observed throughout the winter that the ground was very chilly and warmth retention in that room was poor on the whole. This matches with the way it was insulated beneath – there are 4ft x 8ft areas beneath the subfloor which might be between 10″ joists. These are filled with previous fiberglass which is in poor situation (we knew this once we purchased the home) and there’s some type of low-cost ?fiber board that was suspending the whole lot. Above the fiberglass you may simply see the plywood. I have no idea what’s between the plywood and the ground, however it ain’t sufficient.
As a spring mission, and since I hate cash, I wished to insulate this house higher. Every 4’x8′ house is 10″ deep thus about 300 board ft and there are 12 of those areas so spray foam alone just isn’t an possibility until I pull off the Mega Hundreds of thousands. Would you guys simply do a flash and batt technique?
As a result of it’s open to the air I no less than need some spray foam beneath there, in all probability closed cell, to supply moisture safety. However what ought to I do with the remaining 8-9 inches of peak alongside the joists?
Fiberglass once more? Fiber board? Is it okay to depart a number of the house open (whereas clearly re-sealing it alongside the joists to maintain birds out? Pack it with leaves? Construct properties for stray cats?
Comments ( 2 )
You don’t want to hear this but you want to sprayfoam. get someone to come in and do it. I had a house with perhaps a 20×20 room open to below In the summer it was hot. You couldn’t sit in there during the winter. Just do it. Sure you could pull everything out and put in either blown in insulation or batts but in the long run sprayfoam is the way to go. Let the downvoting begin.
Insulation board has about the same rating as batt or roll fiberglass. I would throw a 2″ board in each of those 4×8 spaces then house wrap across the bottom of the joists. You could put some 1×2 battens over the house wrap to help prevent infiltration into that air space. Probably $800 in materials depending on where you are.