Retrofitting an existing attic to a conditioned attic (without spray foam)
Zone: 3A W/H
Roof Type: 4/12 Gable Roof with Tar paper & Asphalt shingles
I have an existing house I am considering converting to a conditioned attic and have found it fairly difficult to find a feasible insulation strategy that doesn’t involve spray foam.
The problems I have run into …
1.) The house has roof vents and gable end vents, but no soffit vents, so I am trying to determine whether I need to cut in soffit vents and a ridge vent if I do the retrofit or if going unvented is even a possibility.
2.) What insulation assembly to use that would be relatively cost-effective for the relative R-value and feasible to do a retrofit install.
I considered doing something like poly iso boards but that isn’t exactly the most cost-effective approach.
Currently, there is ~ 20in of relatively new loose-fill insulation in the attic I had considered removing it, installing a smart membrane like Intello Plus and then blowing the insulation back into the rafter bays.
Something similar to this…
My concern was depending on what I needed to do with regards to the venting, I didn’t want to potentially pack anything against the roof deck that wasn’t capable of drying properly in the event of any type of leak.
Any suggestions on a sensible way to approach such a project?
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