Is OSB subfloor waterproof?

OSB is strong and water-resistant. Every single fiber or piece of wood in an OSB is saturated with a cocktail of resins designed to provide superior strength and waterproofing to the finished product. This type of board is an excellent material for use in waterproofing systems, be they roof, sub-floor or wall.

Is OSB moisture resistant?

OSB is more water-resistant than plywood. So, OSB can be used for both indoor and outdoor projects. Make sure that you know how to make OSB board waterproof to add barrier against moisture or water.

Can you use OSB for bathroom subfloor?

OSB Subflooring Oriented strand board (OSB) is similar to plywood but the structural differences are what set them apart. However, OSB is known for swelling around the edges when exposed to water. For tile flooring, this can cause bending and cracking, which is why it is discouraged as a subfloor material for tiling.

Which product OSB or plywood is better with moisture and water?

OSB absorbs less moisture, but plywood dries out faster and more completely. But OSB also takes a longer time to dry out, giving the trapped moisture more time to degrade the material than a quick-drying plywood subfloor.

What happens if OSB gets wet?

The wood rot you’re familiar with happens in the presence of water and oxygen. Your framing lumber and the oriented strand board (OSB) are going to be fine. Wood rot can and will start when the moisture content of the wood reaches 20 percent.

Will rain hurt OSB board?

Our OSB is rated “Exposure 1” and that means that it will withstand normal delays in construction. Normal delays and the rain you indicated will not affect the structural properties of the panels. Certainly it would have been better to have covered the roof with a tarp or roofing felt before it rained.

How long does it take for OSB to rot?

Sheets situated so they air dry on both faces between wettings will outlast those that only dry on one side or are always damp. OSB, which is unable to dry out, can rot within a matter of months, while panels that can dry out may last more than a decade.

Can OSB plywood get wet?

4 Answers. OSB won’t be completely destroyed by water, unlike MDF or similar interior laminate materials; however, like any wood product, it will swell and shrink as it absorbs and releases water, so you should typically avoid more than casual contact with water.