How do I prepare a particleboard floor to put down linoleum squares?

You should use a thin , 1/4" plywood. Commonly called luan , but people and places have other names for it.

You shouldn t try to go over particle board or OSB with a self stick or even a glue direct vinyl,

There is to many glues in these types of wood to hold a self stick product well at all.

Any questions you can e mail me through my avatar. GL

2 flooring installers telling what to propely do and you won t do it. why ask?

IF.... the sub flooring isn't warped......You can smooth the flooring out with Durhams Wood Putty. You need to mix it with water in small quantities and fill all the staple holes and gaps between the sheets.

Be sure to trowel off all the excess so you don't have to do heavy sanding... two coats are better than sanding by far.

Then sand it smooth.... vacuum it clean and paint it with an oil based primer.

It will then be ready for your self adhesive tiles.

They only use that type of sub-flooring in modular / mobile homes.

IF it is warped....you will have to remove and replaced those areas first, which is a pain in the backside because they glue it down and use zillions of staples.

When the warped ares are replaced, proceed as mentioned above.

Install a thin layer of plywood by stapling it to the particle board. The linoleum will the stick good to it.