Pine Floor Install

[dwilson37650]

Installing a pine floor in a new addition. Boards will probably be 5-6 in wide. I am wondering how necessary it is to run the boards perpendicular to the floor joist. I would like to run them parallel. The sub floor is 3/4" T&G particle board with 4" of sprayed foam below. There is no basment below. If I don't nail the boards into the floor joist will it be a problem down the road?

[jimbo]

Particle board is hardly a suitable substrate to nail flooring to. And I would fear that you could end up some wavy issues, running parallel.

Any chance of adding some 3/4 plywood on top?

Pine will be beautiful. Be absolutely careful to aclimatize the wood inside the building for a week before install. Be VERY careful to allow expansion gaps around the perimiter on all four walls.

[dwilson37650]

I really can't add 3/4 plywood due to the height problem it would cause. Any other ideas? I may just have to run it perpendicular and live with it. Thanks.

[hj]

The ONLY way to nail it properly will be perpendicular to the joists. Otherwise you run the risk of squeaks and warping.

[Gary Swart]

I don't think there would be a risk of squeaks and warping if you didn't run the boards perpendicular to the joists, it would be a certainty.

[jadnashua]

I would hope the subfloor is OSB, and not particle board. Particle board looks fairly homogenous, OSB has big, discernable flakes and longer slivers of wood. Particle board will blow up like a sponge if it gets wet, OSB, assuming it has an exterior glue, should be fairly stable. Some hold nails as well as or better than plywood, but particle board can shatter.

[dwilson37650]

It's OSB board. Will that hold the nails well enough to go parallel?

[jadnashua]

You'd still be safer running it across the joists.

[Lakee911]

Just to vent, my house was built with BOTH the 1x6 pine/fur subfloor and the 3/8" x 1.5" (IIRC) T&G oak flooring running in the SAME direction, perpendicular to the floor joists. Typically the subfloor is run at an angle. The movement of the subfloor has ripped almost every 4th or 5th tongue off the finished floor. It's a mess. It's a rip up and replace at this point.

I'd run it perpendicular.

See link for same question: http://www.thisoldhouse.com/toh/askt...462454,00.html

[dwilson37650]

Okay that settles it I'm running the boards perpendicular. I would hate to have to redo it in a few years when the boards start warping, squeaking, and ripping out. Thanks to all for the valued advice! (private note to lakee911... Go Buckeyes!!)