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add polyiso
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Fresh Codemonger
Fresh Codemonger
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How old is the house - sounds new as you mention I-Joists.

Concrete and construction water can take a long time to be fully removed from concrete - I think I remember reading 5 years. Is the concrete foundation exposed on the outside to air?

I like the continuous insulation approach as a thermal barrier. Why not use 2x4 on flat instead of your 1x4 grid? I would use 2x4 on flat (assuming the point is to save space otherwise a standard 2x4 wall) with a bottom and top plate on 24 oc and frame that wall plumb. The foam glue should hold the insulation to the wall. Once wiring was finished I'd add more rigid board between the 2x4 on flat. Typically you can run the wires behind the studs on flat as the foundation walls are almost never perfectly plumb. If the wires go through the studs on flat then you'd need to add nailing plates.

I am assuming this is a poured concrete wall. Concrete is a great air barrier so you don't really have to worry about a moisture barrier here though I'd probably go with a vapor barrier paint over the drywall.

Also why not go for the higher R-value of poly iso board (~R6 per inch)?

How old is the house - sounds new as you mention I-Joists.

Concrete and construction water can take a long time to be fully removed from concrete - I think I remember reading 5 years. Is the concrete foundation exposed on the outside to air?

I like the continuous insulation approach as a thermal barrier. Why not use 2x4 on flat instead of your 1x4 grid? I would use 2x4 on flat (assuming the point is to save space otherwise a standard 2x4 wall) with a bottom and top plate on 24 oc and frame that wall plumb. The foam glue should hold the insulation to the wall. Once wiring was finished I'd add more rigid board between the 2x4 on flat. Typically you can run the wires behind the studs on flat as the foundation walls are almost never perfectly plumb. If the wires go through the studs on flat then you'd need to add nailing plates.

I am assuming this is a poured concrete wall. Concrete is a great air barrier so you don't really have to worry about a moisture barrier here though I'd probably go with a vapor barrier paint over the drywall.

How old is the house - sounds new as you mention I-Joists.

Concrete and construction water can take a long time to be fully removed from concrete - I think I remember reading 5 years. Is the concrete foundation exposed on the outside to air?

I like the continuous insulation approach as a thermal barrier. Why not use 2x4 on flat instead of your 1x4 grid? I would use 2x4 on flat (assuming the point is to save space otherwise a standard 2x4 wall) with a bottom and top plate on 24 oc and frame that wall plumb. The foam glue should hold the insulation to the wall. Once wiring was finished I'd add more rigid board between the 2x4 on flat. Typically you can run the wires behind the studs on flat as the foundation walls are almost never perfectly plumb. If the wires go through the studs on flat then you'd need to add nailing plates.

I am assuming this is a poured concrete wall. Concrete is a great air barrier so you don't really have to worry about a moisture barrier here though I'd probably go with a vapor barrier paint over the drywall.

Also why not go for the higher R-value of poly iso board (~R6 per inch)?

Source Link
Fresh Codemonger
Fresh Codemonger
  • 14.4k
  • 2
  • 23
  • 55

How old is the house - sounds new as you mention I-Joists.

Concrete and construction water can take a long time to be fully removed from concrete - I think I remember reading 5 years. Is the concrete foundation exposed on the outside to air?

I like the continuous insulation approach as a thermal barrier. Why not use 2x4 on flat instead of your 1x4 grid? I would use 2x4 on flat (assuming the point is to save space otherwise a standard 2x4 wall) with a bottom and top plate on 24 oc and frame that wall plumb. The foam glue should hold the insulation to the wall. Once wiring was finished I'd add more rigid board between the 2x4 on flat. Typically you can run the wires behind the studs on flat as the foundation walls are almost never perfectly plumb. If the wires go through the studs on flat then you'd need to add nailing plates.

I am assuming this is a poured concrete wall. Concrete is a great air barrier so you don't really have to worry about a moisture barrier here though I'd probably go with a vapor barrier paint over the drywall.