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I am a first-time homeowner and am going through my inspection report to address all issues found. One of them is about attic. It says:

Match R-value of the hatch to overall attic R-value. Upgrade weather stripping.

While the second part is clear, I don't think I completely understand the second part. Attic insulation material is cellulose with an R value of 30. At the same time, the attic hatch is insulated on top with a pink fibreglass batt whose R value is 22-30 based on my quick search. So, in my understanding, both R values already match. What am I missing here? How do I match the value?

Here is a picture of the hatch

attic hatch

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    I often think the majority of people posing as home inspectors are not worth their fee.
    – Ecnerwal
    Jul 29, 2022 at 1:13
  • @Ecnerwal what's wrong with their comment? Jul 29, 2022 at 1:59
  • If the insulation is not compressed, it might already be R30, as you found. But many will flag things not actually in error to make it look like they found something and you feel relieved to have paid their fee. Frequently they also miss the exact sorts of things they should have checked. In this case, if the last paragraph of my answer applies, as it appears likely to me from the photo (but that would have to verified by looking at it on site, in place, from above) it's a much bigger issue than if the center of the hatch is R22 or R30, because it might be about R1 for that strip.
    – Ecnerwal
    Jul 29, 2022 at 2:19
  • @Ecnerwal you were right: insulation is not compressed, and weather stripping is in very bad shape. So, just changing weatherstripping and installing latches to create compression will do. Jul 29, 2022 at 4:59
  • The intent, I suspect is to suggest there's no gain to making the hatch insulation any greater than for the rest of the attic floor, for obvious reasons. Jul 29, 2022 at 16:58

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If the hatch construction is such that the insulation is compressed rather than fully expanded, if might be running closer to 22 than 30.

That makes far less difference (in a large area of R30) than the air leaks, if the weatherstripping is actually bad.

Replace the boards holding it in with foamboard insulation or stick a scrap of 3.5" fiberglass on there (over the boards) if you like fiberglass better.

I have more of an issue with the fact that it appears as though it fits rather loosely in the hole, which (if true) leaves an uninsulated strip all around it. If the sides of the hatch are the same height as the framing around the hole, adding top insulation that overhangs the gap (covering it from the top) would reduce that issue significantly.

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