On Jun 13, 8:52 am, DerbyDad03 wrote:
On 12 Jun, 22:51, wrote:

So, I want to redo the floor in a cheap little cabin. The subfloor is
particle board, covered with linoleum tile, subsequently carpeted.
I've removed the carpet and tile (shingle rake was helpful for that).
The particle board has gotten wet in some places and softened and
gotten lumpy, and doesn't smell very good. I'm thinking of trying to
seal it with some sort of paint or varnish or something, before
putting a plank floor on. Something that would soak in and harden and
restore some integrity to the soft spots, and seal in the musty
smell. Anyone have an idea as to what might work, or general advice
on dealing with particle board subfloors?

Devil's Advocate checking in...

Define "cheap".

Determine the cost of replacing the entire floor with plywood,
finishing the plywood and caulking around the perimeter and compare it
to the value of the cabin itself. Is it worth it?

Consider the condition of the rest of the cabin. Are there other parts
of the cabin that are also poorly built and will need repairing in the
near future? If cost effective, it might make sense to include those
"uprades" as part of this project. If not, it might not make sense to
put extra money into upgrading the entire floor in an otherwise crappy
building.

Consider the construction method of the cabin. Are the exterior walls
built on top on the particle board subfloor and if so, what is the
condition of the particle board under the exterior walls? Will you be
replacing the interior floor section, while the integrity of the
building itself is in question because the floor under the walls is
rotten?

At the highest level, I agree with everyone else that a particle board
subfloor sucks and that it should all be replaced with plywood. On the
other hand, the cost of the new floor has to be weighed against the
value of the building (before and after) to see if it makes sense.

If I was worried about moisture, I'd go cement board. But if the OP
just replaced the particle board that was bad, and used sheet vinyl
instead of vinyl tiles, just making sure the edges were well glued, I
doubt he see any more problems.