Can I seal particle board?
You could apply a sealant to particle board. And, depending on the number of coats you apply, it may even ward off moisture for a while. However, particle board isn’t intended for use around wet conditions. The sealant will eventually break down as the board expands and contracts and the chemical-base looses it’s strength. If you notice, even in kitchen cabinets and bathroom applications, particle board is always covered with some sort of laminate or other water-proofed material. And, this is for interior use, let alone any exterior applications, where drastic changes in temperature would also play havoc. I would avoid using particle board in a situation that calls for water-proofing. JMHO If you must find a way to water-proof it, I wouldn’t go with tiles (they would have grout lines or other areas which would allow seepage of water/moisture. You could try to use some kinf of solid laminate like that used for bath or kithcen flooring (it’s a continuous piece without any lines or breaks
