Osb subfloor which side down

But checking with the manufacturer is of course the best bet. Let us know what you find. Shawn I just called APA. They provide approval for most wood structural panel OSB and Plywood. They stated that they do not have special requirements for a specific side up or down. However, they stated that some manufactures like to have the rough side up for safety issues. Just spoke to Norbord Two reasons for "This Side Down" 1 Safety- One side has a screened finish rough 2 Inspections- Easy for the Building Inspector to identify the sheathing with the approved stamp looking from below Thanks for everyone's input!!

The stamp is on the smooth side, which will mean the rough side is up on roof rafters or trusses. Bold text mine. So I suspect, as stated earlier, that it is safety and that the "this side down" side is the smooth side. Yes Russell… That is exactly what the manufacturer said Norbord. See post two up from yours. Good link! As previously stated, building inspectors want to be able to look up and see the stamps, the other reason is there is a special coating on the non stamped side that is suppose to be water proof sealer.

Feel Free to look at the www. OSB roof panels should always be installed with the grade stamp facing into the attic and the screened surface with the nail guide lines facing up.

When the grade stamp is covered by roofing, the building inspector will not be able to confirm that the correct OSB roofing panel was used. The screened surface also provides a little more traction for construction workers during installation.

The same goes for wall sheathing and flooring panels; always install with the grade stamp up so that inspectors can do their jobs easily. The strength axis is usually the long direction of the panel but the grade stamp will indicate it. Be very careful on hip roofs along the hip to make sure the strength axis does not mistakenly get parallel to the supports as that may result in the panel exceeding the maximum span allowed for that thickness.

Instead they can view it from a basement or lower floor where the ceiling may be left unfinished and have the OSB exposed. It is important to rely on the stamping on OSB as a guide during installation.

This is mostly for roofers so that they lay the smooth side down and can stand on the rough side facing up. The smooth side has a better moisture resistance and will ultimately provide better performance against weather.

Facing the board smooth side out will maximize its ability to keep moisture out of the structure. It is simple why manufacturers create roughness on OSB boards. Without this added feature, being a woodworker would be more dangerous and the job would be more difficult. We dig deep to find the deals you need to help your business grow. We provide these deals in two ways for you to access. Our Web Specials are posted regularly here on our website. Our QuickBuys 2.

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