Insulating a cantilevered space that is sealed, no easy access
I screwed up. I had the opportunity to add insulation when the space was open but just didn't feel it was that important. I have a cantilevered space, bedrooms above and porch below. It's been hot lately and I can feel a difference of around 10d when measuring the floor over the porch vs the floor over a room. The cavity between floors is 8" when above a room but 18" in the cantilevered space. The top 8" of the cantilevered space has joists while the bottom 10 is pretty much unobstructed.
Accessing from the inside is a no-go as I believe there is a beam that runs the length of the interior wall. Access from teh upstairs floor will lead to some great pain as they are new floors.
Two options (maybe you guys have more):
Option A: Access from the porch might work if there is an insulation I can use given the walls don't have any moisture barrier. I could make 4" holes, maybe 10' apart, in the porch ceiling then blow something in (several feet on either side of the hole, to fill the space? I would then add lights where the holes were.
Option B: I might be able to remove the exterior siding (one or two boards) then add the insulation from the outside. I would need to have some new pieces milled but access would be greater.
Thoughts appreciated.
Pic 1 Bedroom Floor A - Bedroom floor, showing the 18" of space
Pic 2 Bedroom Floor B - Bedroom floor, showing the same cantilevered space. Hard to tell but it is an "L" shape and about 2/3 of the that room.
Pic 3 Outside view to illustrate the space
