sort of on-topic: hardwood floors, particleboard underlayment

This is sort of woodworking, in that wood is involved.

I'm looking at tearing out some carpet and installing nail-down solid hardwood. I've done some research and it appears that my existing floor consists of 3/8 particleboard on top of 5/8 plywood. I've heard anecdotes about water spills causing the PB to swell and ruin the floor...anyone know for sure if this is an issue?

Do I need to rip out the particleboard (and maybe add a layer of 3/8 plywood) before installing the hardwood, or would it be kosher to put the hardwood on top of the particleboard?

The particle board will swell if wet. This is more of a problem with vinyl floors because they are in fact porous and water will destroy the substrate that they are glued to(the particle board). You problem with particle board is nailing your hardwood floor to it. The particle board will not hold nails. If this is the floating floor type of hardwood then you only have to worry about the water and swelling. Particle board was an attempt to provide a very smooth subfloor which it did provide, unless it got wet.

Whatever you decide on, use felt under the flooring to prevent squeaks.

If you're laying hardwood planks perpendicular to the floor joists, then you should only need that 5/8" layer of plywood for support. I'd take the particleboard out (so there's no chance of water getting into it).

If you're laying panks parallel to the joists, you'll want another layer of plywood for support.

I can guarantee that particle board swells when wet, and hunks stick to the flooring when removed. Perhaps this is in an area that never got wet?

Would the addition of 1/4" plywood over the particle board raise the floor level too much?

I would not tempt fate with particleboard. Nobody ever plans for a water damage incident, but they happen. Leaky pipes, overflowing toilets, sinks, showers, tubs, roof leaks, etc.

If you get water damage, the particle board will swell. This will require ripping out the hardwood and the sub floor.

If I were you, I'd get rid if the particleboard. It could save you thousands of dollars in the long run.

Thanks guys...I was leaning towards ripping it out, but wanted to make sure I wasn't erring too far on the side of caution.

Given that in at least one room I'll be going parallel to the joists I think I'll be ripping it out and replacing it with plywood.

Quote:

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Originally Posted by Robert Strebler

I would not tempt fate with particleboard. Nobody ever plans for a water damage incident, but they happen. Leaky pipes, overflowing toilets, sinks, showers, tubs, roof leaks, etc.

If you get water damage, the particle board will swell. This will require ripping out the hardwood and the sub floor.

If I were you, I'd get rid if the particleboard. It could save you thousands of dollars in the long run.

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I'll add one more vote in support of this position. Personally, I hate the stuff.

I don't know about water-related problems (obviously bad), but I just installed a hardwood floor and there were cautions everywhere, including voiding warranties, not to put a nail-down hardwood floor over OSB or particle-board because the nails don't hold sufficiently well. I believe there was one special variety of OSB mentioned as acceptable in only one article.

i do this for a living for the past 20 yhears or so rip out the particle board and since it is 5/8 ply i would recomend adding a layer of 3/8 or 1/2 cdx ply then installing the hardwood

I don't install hardwood floors for a living but I did put in several hundred square feet in my house last summer. Never having laid a new hardwood floor I tried to learn everything I possibly could about the process so I could do it right the first time. We were intending on putting in carpet before we decided to go with the hardwood so I had already put down the new particleboard with ring shank nails and really didn't want to take it up if I didn't have to. Without exception, everyone who were familiar with installing hardwood floors I talked to said do not use particleboard. So I pulled up the new particleboard , installed plywood, and felt good about doing the job right. :cool:

Terry