How To Look At A House
McGarry and Madsen's home inspection blog for buyers of
site-built, mobile/manufactured and modular homes
What does lack of tab adhesion in an asphalt shingle roof mean?
Monday, September 3, 2018
Asphalt shingles are nailed to the roof sheathing below along the top edge of each strip of shingles, which is covered up by the row of shingles above it. But the exposed bottom edge of the shingles has adhesive strips that secures them in place and prevents the shingles from being lifted up by a gust of wind. Over time, usually starting at about 15-years old, a 3-tab shingle roof starts to lose its adhesive grip along the bottom edge. This progresses as the roof ages, with the edges starting to curl (shown in the photo below), until the bottom edge of the shingle is loose.
As the shingles become more brittle with age, any lifting of the leading edge by wind causes part of the shingle to snap off, exposing the nails below. Exposed nails holes are points that will leak.
Also, when shingles are beginning to lose adhesion, the exposed edge can be lifted up by hand and it makes a soft tearing sound. As they totally lose adhesion, lifting makes no sound at all. Checking tab adhesion is one way that a home inspector evaluates the condition of a shingle roof.
Also, see our blog post Why is premature curl of roof shingles a problem?
• • • • • • • • • • • • • • • • • • • • • • • • • • • •
To learn more about roofs and attics, see these other blog posts:
of Blog Posts
Top 5 results given instantly.
Click on magnifying glass
for all search results.
Buying a home in North/Central Florida? for a team inspection by two FL-licensed contractors and inspectors. Over 8,500 inspections completed in 20+ years. In a hurry? We will get it done for you.