What Causes Roof Shingles to Buckle?

Well, that’s definitely NOT good! What’s going on here?

This is what we call buckling. Shingle buckling is one of those awful things that can happen to a roof through no fault of anyone. It is caused as a result of the movement of the wood roofing deck or wrinkling of the underlayment. And this is a serious problem because if minor buckling is not addressed, it could require a full roof replacement.
roof with shingles buckling

Common Reasons for Buckling

Most roofing companies in Salt Lake City, Utah have experience with this issue. But what causes it? Here are the most typical reasons:

  • Exposed deck: When the old roof is torn off, the wood deck is exposed. When there is a high percentage of humidity in the air, the wood can absorb some of this moisture. As the moisture content in the wood increases, it case cause the deck to shift and move.
  • Wet underlayment: As a new roof is being installed, if too much moisture is absorbed by the underlayment, it can cause the felt to wrinkle.
  • Improper venting: If your attic does not have enough vents to allow for the circulation of air through your attic space, the hot air will have no way to escape, and can make the wood shift or the underlayment wrinkle. Higher insulation levels may necessitate additional vents.
  • Roof sheathing: If your roof deck is not spaced adequately (a minimum of ⅛” between boards), the natural expansion and contraction of the wood will cause the shingles to buckle.
  • Improper materials: If wood decking has not been properly conditioned to be at moisture equilibrium with the environment in which the job is being completed, the natural expansion or contraction can cause buckling. This is a roofing manufacturer’s approval that must be met.
  • Improper installation: Failure to apply shingles as directed by the shingle manufacturer’s recommendations.

If you see anything looking off with the way your shingles are laying, give your trusted roofing contractor a call and have your roof checked out right away.