Newbie here with a particle board question, LOL...
My daughter has bought her first home it has 2'' x 10" joists 16" OC, there is I/2"plywood with 1/2" particle board nailed over the plywood. She has a limited budget with time and money. The plan is to screw down the existing particle board and plywood to the joists then attach the 3/4" new tongue and groove hardwood flooring over the particle board. I know this may not be the best or recommended way to go but it is what she can afford at this time. So my question is should we use an underlayment that is stapled to the particle board and then use an adhesive plus 2" staples for the finish flooring? Or should we forget the adhesive altogether? Without removing the particle board we are looking for the best way to go without tearing up and replacing the particle board.
Thanks,
Dan

rip up the particle board. trying to save a couple of bucks now will cost her much more down the line. I use a cats paw and remove the nails first which allows me to remove a whole sheet at once. It takes me about 20 minutes per sheet. Then put down another layer of 3/8 plywood. It only costs less then $25/sheet so unless she is doing thousands of sq ft It won't add up to much compared to replacing the entire new floor later on.

I have told her till I am blue in he face to remove the particle board, she refuses. I have been in construction for over 30 years doing paint and drywall so I also know what a cats paw is and have super bars, pry bars and all the tools necessary to remove and reinstall plywood. SHE is adamant about leaving the particle board! So what is the best approach given the plywood and particle board she has? I even suggested priming the particle board with a long oil interior primer to seal it, NOPE she doesn't want to do that either.. I explained to her that the floors may need to be leveled using a 'self leveling' thin set which I don't think can be done on particle board either. Any other suggestions, anyone???

I would secure the particle board as you outlined.

Use 2" fasteners for the flooring and buy a quality urethane adhesive and strip glue every 16" between joists.

mark out the joist line and drive fasteners of the flooring to the joist.
the fasteners are long enough to go through the particle board as well penetrate the 1/2" ply.

the nails will hold to the plywood.

the gluing will certainly add rigidness to the install.

I see no failure down the road doing it this way.

use some shellac to seal the particle board as your vapor retarder.

I'm not sure about all the fuss to not remove it..I suppose it will cost her nothing for you to do it since she's your daughter.

You could always just remove the particle board and install directly to the 1/2"

there is nothing against guidleline for that.

you can then just use a felt underlay or underlay of choice.

Nail to the beam and inbetween and you ill be fine.
you can also skip the underlay and do the glue nail but this is all really overkill.

1/2" subfloor is acceptable for hardwood install.

Ahhh, Shellac one of the best & oldest primers ever conceived. I have used it for years, the only thing I find to whine about is cleaning my tools with ammonia. At least that's cheaper than denatured alcohol, non flammable and can be dumped down the drain! I was planning on locating the joists and screwing through both the particle board and the plywood with 2" coarse thread drywall screws.
If I understand correctly your recommending adhesive and fasteners for the finish flooring and the shellac primer to seal the particle board? I'll do a search on strip gluing as I don't know what that is. We are going with 2" staples for the install, I know there may not be much of the staples hitting the joists given the angle/subfloors and am hopeful that the 1/2" plywood will secure things as well as can be expected. Believe me when I say I'd remove that particle board in a New York minute but her finances are tight. It's her first home and sometimes you have to do what you can and hope for the best!
Thanks for the advice, this Dad appreciates it!

just put a bead of PL premium or buy a pail of urethane adhesive and trowel on strip every 16 inches..go between the joists

and nail your floor to the beams and between