Soft Plywood On Roof

Severe weather 1 2 in common douglas fir plywood sheathing application as 4 x 8.

Soft plywood on roof.

In roofing plywood is often selected due to its strength. Without good attic ventilation your roof gets extremely hot. Most roofs have plywood sheeting underneath the roofing tiles or shingles. These soft spots usually form when the layer underneath gets soaked due to gaps in the shingles.

Over the period of manufacturer s designated roof lifetime of 25 to 30 years that plywood is exposed to heat in the summers heavy rains and the winter weather and cold dampness it brings. Inadequate attic ventilation can also cause your shingle roof to feel spongy or bouncy. This can be a result of the plywood sheeting becoming wet from rain above or from moisture not being able to escape from below and leading to mold mildew growth on the wood. Plywood will weaken over time sometimes softening in places where the wood has gotten damp because of those gaps.

Roof decking is the material that lies on top of the main roofing structure and the underlayment and roof covering is applied on top. And that extreme heat can damage both your shingles and the wood decking below them and causing your roof to feel soft when walking on it. The reason for these soft spots is that the layer underneath is probably very soaked due to gaps in the shingles cause over time and weather changes and the water is seeping through the sheeting. If you can tell there s a soft spot on your roof this most likely means that the substrate below the roofing material is damaged and deteriorating.

Take off the roof covering which usually consists of plywood screwed into the rafters and walls. When used in flooring plywood functions as the subfloor that supports hardwoods tile and carpet floors. Why is plywood used in roofing. In roofing plywood can be used as roof decking.

Do not cut into the roof rafters. When used for roofing plywood panels are covered and protected by a variety of building materials that keep the elements at bay including roof felt underlayment flashing and shingles.