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Insulating hard to access attic space

Monster_Hair | Posted in General Questions on

Hi Everyone,
In a little while I’m going to have my roof replaced. When the shingles are all off, it’ll allow me access to a remodeled section of the attic. Sometime in the past they added a better entryway, with a low pitch roof add-on. So, the pitch is low, there’s zero access from the rest of the attic, and I’m pretty sure it’s either underinsulated or uninsulated. When the shingles are off, I then can access this section and add insulation. Now, here’s the question: what kind of insulation to go with? I had been thinking to almost fill up the whole space with blown in cellulose, but that would be not very effective on the thin side. So, then… rigid foam has much higher R/inch values, but does not do as well with water vapor. So, maybe open cell foam instead?


I’ll be air sealing before I do anything, btw.


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  1. GBA Editor
    Brian Pontolilo | | #1

    Hi Joel.

    Where is the house located? How much room is there from the attic floor to the underside of the roof? Is the space vented? How is the rest of the attic insulated? Can you post a simple section drawing of this attic space?

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