Plywood Under Roof Is Soft

From our article anatomy of a pitched roof.

Plywood under roof is soft.

Instead it is used to hold concrete whilst it sets. Your whole roof or large sections of your roof are bouncy and your home was built prior to the 1990s. Osb and plywood come in thicknesses ranging from 5 16 to 3 4 inch and the thickness needed for a particular roof depends on several factors including rafter spacing expected load and roof design. Both osb and plywood for the roof have been approved for use so it may come down to what you feel most comfortable using.

General plywood does not have this proof of strength performance so should not be used for structural applications. Rafters run from the peak of the roof. These soft spots usually form when the layer underneath gets soaked due to gaps in the shingles. While it s not the main material for the roof itself roofing plywood is an important part in a roofing structure.

Most roofs have plywood sheeting underneath the roofing tiles or shingles. The anatomy of a shingle roof. The underlayment and shingles are attached to the decking. Plywood decking sits on top of your rafters.

Choosing the right type of plywood for the roof is one of the most important construction decisions that you will have to make. Most roofs have plywood sheeting underneath the roofing tiles or shingles. Generally plywood comes in 4 by 8 foot sheets and in a variety of grades. If you think the roof may be weak or do not want to take the risk of going up on your roof have a professional examine it instead.

Shuttering plywood is another type of plywood but it generally isn t used in roofing. The minimum plywood for roofing. It determines how long your roof will last and how well it will protect the contents of your home. Over the period of manufacturer s designated roof lifetime of 25 30 years that plywood is exposed to heat in the summers heavy rains and the winter weather and cold dampness it brings.

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. This is likely your problem if. 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. You may choose to get up on your roof if the pitch is not too steep which will allow you to feel for any sponginess in the plywood as you walk across it.

Roofs are framed with rafters or trusses which are rafters joined by internal braces so they install as a single component.