AskARoofer.com > Our Forums > AskARoofer > Exposed Underlayment Attic

Exposed Underlayment Attic

Viewing 2 replies - 1 through 2 (of 2 total)

Author

Posts

November 6, 2025 at 1:29 a.m.

HannahFord7

Samantha from Montana asks: We recently had a house fire and have gutted part of our 1916 house. We just had new asphalt shingle roof put on less than two years ago. I noticed once they demolished the ceiling into the attic I could see the underlayment from the roof exposed in multiple areas. Is this normal? Should plywood have been added to the roof?

November 6, 2025 at 1:30 a.m.

HannahFord7

Below is what our roofing expert John Kenney with Cotney Consulting Group had to say in response to your question:

Samantha, seeing roofing underlayment from the attic is not typical in a roof assembly. In a properly built roof, the shingles should be installed over solid decking—usually plywood or OSB—which serves as the structural base for the roof system. The underlayment, whether felt or synthetic, is applied on top of that decking, directly beneath the shingles.

If you see the underlayment exposed from inside the attic, it likely means there’s no solid sheathing under the shingles—something more common in homes built before the 1940s, when spaced plank decking was standard. While older roofs can technically be reroofed over those boards, there should not be significant visible gaps exposing the underlayment. Gaps that wide can compromise shingle fastening, insulation, and performance.

Given your home’s age and the recent fire damage, I’d recommend having a qualified roofing contractor or structural professional inspect the deck. They can confirm whether new sheathing should be installed over the existing boards to meet current codes and ensure long-term roof integrity.

Thank you for using AskARoofer! Find more resources to answer your roofing questions here: podcasts, articles, previously answered questions and more!

November 6, 2025 at 1:30 a.m.

HannahFord7

https://www.youtube.com/embed/h5yP13MA78Q</a>" title="Exposed Underlayment in Attic" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen>

Viewing 2 replies - 1 through 2 (of 2 total)

« Back To AskARoofer

You must be logged in to reply to this topic.