Hot answers tagged underlayment
I hate to be the bearer of bad news, but particle board is not a good choice of subfloor, unless it has gotten better over the years. (It has, at least in Australia, see edit below)I asked the question of floor suppliers and here on SE about fastening flooring to particle board with an answer that said nobody will guarantee the floor will stay in place. ...
The goal is a smooth, flat surface for the vinyl to lay on. If you can do that with 1/4, then that is great. But in your case it sounds like you need to step up to 3/8 or 1/2 depending on the gap. Once you put that down, then there is no need to add 1/4 plywood.
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