Hi new here and it's a great site. What do you guys think of this subfloor for installing a hardwood floor on? It's 1/2" plywood with 5/8" particle board glued and nailed over the plywood. Floor joists are 16" oc. House is 20 years old and the floor would be installed over a 5 block crawl space and also a finished basement. Thanks!

just curious, how did you determine that it is glued down. I have not torn out any that was glued to 1/2 CDX plywood.

You should not install any mechanically fastened hardwood flooring over particle board.

The particle board has to go.

Lots of DIY'ers get OSB, which is OK, confused with particle board, which is junk.

Jerry T, I put it down 20 years ago and I remember using a ton of glue. It's a very sturdy floor as far as squeaks and it being flat goes.

Floorguy, I've never done any hardwood floors but for a living I buy houses in need of repair, fix them up and resell them, so I do know the difference I was just hoping with the two different floors and being glued together it would be good enough. I just removed the kitchen underlayment and all of the staples stayed in the particle board.
No way I'm tearing out both floors. I guess it's back to carpet Thanks guys

You could install a floating hardwood floor over that p. board; or a gluedown as well.