Roof Plywood Buckling

Your roof decking is the plywood sheets that cover your home.

Roof plywood buckling.

Less likely as a cause of a buckled roof is poor attic ventilation. Ripples or waves on the roof surface are a sure sign that the shingles or decking has probably buckled. Continuous roof vents stationary roof vents turbine vents and power attic ventilators are just a few. Improper installation of roof sheathing panels can result in warping or buckling of asphalt shingles.

When these boards are not properly fastened and nailed to the framing they can buckle as well. On occasion poor attic ventilation can cause the sheathing to become warped from underneath. For a good reason. Plywood and osb roof sheathing are the most popular roof sheathing materials in the u s.

They are easy to work with readily available and perform the job well. When plywood or osb sheathing picks up moisture it expands. These ventilating systems work in conjunction with adequate soffit ventilation. If the wood structural panels are tightly butted there is no room for expansion and buckling can occur.

Plywood and oriented strand board osb like all wood products will expand or shrink slightly with changes in moisture content. If the adhesive side is not laid properly and not applied flat it will surely show its buckling through the roof shingles. This happens most often in hot and humid climates. But they must be installed correctly.

Occasionally the buckling is caused by poor workmanship wrong materials or possibly by a problem with the structure itself. Buckling of wood structural panel sheathing such as plywood or oriented strand board osb occasionally results when increased moisture conditions cause the wood to expand. Such buckling may occur between supports or between nails along supports. Call your builder and have him fix the buckled plywood.

The most common cause appears to be movement in the roof sheathing with changes in moisture levels. However warped plywood sheathing means the entire roof has to be replaced immediately or it may collapse. Roofs buckle because either the roofing underlayment has wrinkled or the wood deck itself has shifted for some reason. Your builder is responsible for providing adequate soffit ventilation.

If the sheathing is properly gapped then the gaps can close causing the shingles spanning the gap to buckle.