Waterproofing Particle Board Floors

Hi all,

I have particle boards installed in my second storey (green tongue) and would like to get them waterproofed before installing the carpet.

There is a bathroom and toilet upstairs so I would like to protect the particle boards in the event of flooding and eventual rotting of the boards (even if a drink is spilled, I want to protect against molding as I wont be able to lift up the carpet and replace the boards). The particle boards are also screwed under the steel framing walls so cannot be replaced.

Glad to hear any recommendations on how to waterproof particle flooring? Or recommended products to DIY a waterproofing membrane? e.g. Gripset.

Gripset is water based though, so I'm unsure if it is suitable for particle board floors.

Thanks everyone, look forward to your advice.