Rot Resistant Roofing Osb

Solid wood rafter tails on the exposed underside of roof eaves having a minimum 2 nominal dimension may be unprotected.

Rot resistant roofing osb.

The exposed roof deck under unenclosed eaves and underside of porch ceilings shall be noncombustible listed ignition resistant materials or 5 8 type x gypsum sheathing behind exterior covering. If you re using a wood outside starting with a rot resistant wood is the most important step. Cbc 706a crc r337 6. Compounding this weakness is the fact that osb is often made from aspen and poplar which are not rot resistant woods.

With a weather resistant barrier like tyvek over the osb and then cover that with siding of some sort. Osb will swell warp and degrade unless it s kept safe from sunlight and perfectly dry. After following these steps you will never risk moisture ruining your work down the road. When a wood is in direct contact with the ground it opens the wood to mold and fungus because it allows moisture to penetrate the wood.

Sheets made from aspen or poplar which are common have more rot susceptibility than those made from rot resistant species. So how do you stop wood rot in those cases. Since osb holds water prolonged exposure to roof leaks or excessive humidity and condensation in unvented attics can cause osb roof panels to degrade faster than plywood panels. No paint will do this.

There s no such thing. 8 rot resistant woods naturally resistant woods that are commercially available include black locust robinia pseudoacacia teak tectona grandis ipe tabebuia spp california redwood sequoia sempervirens and bald cypress taxodium distichum. These have the highest resistance to rot over time. How to stop or prevent rot.

If you want to use osb to sheathe the walls of your shed you need to build those walls like the walls of a house. The zipsystem is a great all in one osb sheathing panel that has the building wrap already attached to it so all you have to do it tape the seams. Osb is said to be more water resistant than plywood by some and not so by others. It s installed directly on the roof deck and provides a secondary layer of protection from the elements including rain snow and wind.

Because osb holds water prolonged exposure to roof leaks or excessive humidity and condensation in unvented attics can cause osb roof panels to degrade faster than plywood panels. The resistance of osb to rot depends on the material from which it is made. Compounding this weakness is the fact that osb is often made from aspen and poplar neither of which are rot resistant woods. Even rot resistant woods can become vulnerable over time or with extreme conditions.