We are wanting to replace carpet in our 30-year old house with a hardwood product. The subfloor is plywood, with a particle board underlayment. All the research I did indicated that you cannot install 3/4" hardwood over particle board, so we considered laminate and then engineered. When the installer (with 30 years experience) came out to measure the job, he said that he has installed 3/4" over particle board by using 3" staples that penetrate the particle board and fasten to the plywood. Has anyone else done this? Does it sound feasible or am I just aking for trouble down the road?

umm, ok I've been on jobs were we went over partical board, Many many times. I've worked for a few people in the trade, Some would Never never never ever do it. The others (1 or 2) would do it in a heart beat. As far as I know their hasn't been any trouble with it.
What would I expect from a partical board install, If water ever penetrated the floor forget about it the partical would swell. Maybe down the line you could get squeaks as partical board doesn't hold the staple to good. From what I think I read you have plywood over partical board. I never incounted this, As far as staple lengths. I've seen 2" never 3, If you do go ahead just make sure you cross your t's and dot your I's, Make sure the staples are indeed 3" and make sure you get something in writing as far as the installition goes.

I am not aware of any 3" staples that will fit ANY of the flooring staplers. They are all made for 2" staples and less. Furthermore, both the NWFA and NOFMA recommend against nailing to OR through particle board. Why not just remove it? How thick is the plywood subfloor. If it is 5/8" plywood over joists 16" oc, that meets the minumum standards for 3/4" strip flooring.

Thanks for the replies. It reinforces what I thought I understood from this website and others. The plywood is only 1/2", so it appears my only options are laminate or engineered, or can I take out the particle board and add more plywood? What are your opinions about laminate and engineered?

I'm in the process of nailing 3/4" prefinished directly on particle board. I noticed a professional who did my neighbor's house did the same thing.

I did notice that there was one section where the previous owner apparently had a water leakage problem coming down the wall, and that the particle board was rotten and slightly swollen where it had met it. I tore that up and put in a new particle board, then laid down felt and am in the process of nailing down over it all.

Just because he got paid, does not make him a professional. In this case, we call them HACKS. They give true flooring craftsmen a bad stereotype, by association.

Plan on a squeaky loose floor in the near future!!! Guaranteed! Oh well, what do expect from DIY flooring installs.