New porch floor insulation NH – GreenBuildingAdvisor

Hello

Hoping to reduce labor and simplify floor insulation. Considering:

Wood floor over rubberized underlayment on subfloor sheathing,

2 inches high density rigid foam on top of 2×10 joists filled with 9.5

rockwool. Bottom layer to enclose.

Addition on piers 4ft off ground, open.

1) Pt or cdx to bottom of joists.

2) Rigid foam 1&1/2 or 2 inches to bottom of joists then

pt or cdx?

3) something other than rigid foam under joists, before the

pt or cdx? Perhaps some advanced vapor/air barrier?

Small porch, nothing heavy, few chairs and small table.

Really attempting to reduce all the labor with rigid foam between

the joists, then sealing all around each piece with expanding foam.

We will be insulating the rim joists.

Appreciate the comments and suggestions.