Is OSB OK in the rain?

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.

What happens if OSB board 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.

Are OSB boards waterproof?

And what happens if they get wet? As a general rule, most OSB are water resistant. Due to their construction process using wood strands, resins and wax they come fairly water resistant.

How do you protect OSB from rain?

How to Protect OSB from Rain

Step 1: Ensure Your OSB Is Waterproofed. Check whether your OSB has that ‘waterproofed’ stamp on its surface.
Step 2: Plan and Cut Pieces.
Step 3: Paint If Necessary.
Step 4: Apply Waterproofing.
Step 5: Test.

Could OSB be better than plywood?

OSB offers more consistent quality than plywood because there are no core voids and OSB will not delaminate. Plywood is also more likely to delaminate when exposed to moisture than OSB. No matter your inclination, OSB has become the building material of choice for North American professionals.

Can OSB get dry rot?

Yes, OSB or Oriented Strand Board, can get dry rot. This is because it has a fault in that if it gets wet, it majorly expands. It can expand up to 15 percent, and never go back to normal.

Can You waterproof OSB?

OSB is often waterproofed before being sold in stores. However, if you’re planning on using this wood for an exterior project, you will need to add additional moisture protection.

Is OSB board safe?

OSB is safe to use. Resin binders and waxes are completely cured and stabilized, so there is no measurable off-gassing from panels. roofing contractors prefer this product for it’s nationally recognized safety record.