I remember back in the 70s and 80s, 5/8" particle board was the underlayment of choice for carpeted areas in new construction. Does anyone know if this is still the best choice over a 3/4" T&G subfloor?

Thanks

mwarney,
Use 3/4" TG Plywood. It is code and will last.

All the best,

The PorchGuy

Hey thanks! Do you mean I should just install the carpet on the subfloor then? I know I wasn't clear in my question but I already have 3/4" T&G subfloor installed over the joists. I need to know what (if anything) I need to put down on top of this for underlayment. Like I said, years ago we used the 5/8" particle board but I think the subfloor back then was only 1/2" rough plywood.

Thanks again for your response!

You need to add a sub floor to it if you only have one on there now. When we build house well sheet the whole floor but go back and add hardwoods and other plywood for use carpet areas.

mwarney,
Using the 5/8" paticle board will be adequate over the 3/4" T&G plywwod.

The PorchGuy

It's a matter of preference, as is the case with many other methods of work.. yes, particle board is still used under carpet, as is 3/4" T & G! There's something cleaner and smoother about particle board... but under the padding and then carpet?? do you think it will make a difference? Some folks think so. If it were MY house? Particle board, absolutely.
G.P.R.