Hi everyone. I am installing 3/4" solid hardwood flooring down throughout my house. My current subfloor is very solid 1 1/2" tongue and groove planking, installed perpendicular to the floor joists. Very solid to walk on with no deflection.

I have decided to raise the height of the floor 3/8" to make for better transitions to tile and some entryways. I am faced with a choice - use plywood or OSB.

I would prefer OSB because of cost (1/3rd the price). I am using 2" cleat nails, so the nails would go through the OSB and imbed into the TNG anyways.

I've done some research and several studies show nail head pull-through is actually better with OSB vs. plywood, meaning nail perform better in OSB than plywood.

However, I want some second opinions.

Please chime in! I'd love to pick up the underlayment today.

I would use plywood if I was you. I don't know what study that was, but I have a feeling it wasn't 100% unbiased.

You are making a big investment as it is, I don't think it's worth risking dollars a square foot to save cents a square foot.

I've seen quite a few floors that failed because of OSB underlayment so, I might be a little subjective on the matter...