Bathroom subfloor - part chipboard, part plywood. Should I SBR it?

[mjgreen81]

Hi,

Im replacing about 30% of our bathroom floor due to some water damage. I'm going to be using 18mm plywood to replace the previous chipboard. The rest of the floor will remain 18mm chipboard.

After the subfloor is repaired im Ilkley to be building it up with another 6mm of plywood (where it is needed) and then laying either LVT or vinyl (we won't be tiling).

Do I need to SBR the plywood subfloor even if I'm not tiling the floor? Will this help protect it if I have future leaks?

Should I SBR both sides and the edges?

Can I/should I SBR the remaining existing chipboard floor to help protect it in the future? Will i risk damaging it if I SBR it?

Thank you

 

[noseall]

SBR will only do so much. Don't expect a coating of SBR to perform exclusively as a DPM. It's primarily a bonding product. It won't damage the chipboard, however.

 

[mjgreen81]

SBR will only do so much. Don't expect a coating of SBR to perform exclusively as a DPM. It's primarily a bonding product. It won't damage the chipboard, however.

I guess my query is whether it's worth doing it if I'm not using it as a bonding anything to it.

 

[noseall]

I guess my query is whether it's worth doing it if I'm not using it as a bonding anything to it.

It can help stabilise the surface of the chipboard - yes.

 

[Ivor Windybottom]

Are you gluing the tiles or vinyl? If so then the glue may or may not be compatible with SBR - they may peel apart.

You'd usually fully cover the floor in adhesive anyway, this probably benefits from being able to soak into the wood and bond securely to it. And it will stabilise it anyway.

Loose lay vinyl is usually terrible, especially if you're going to cut around toilet, pedestal etc. You'll end up with bulges and bumps if not glued.

I put commercial grade vinyl in mine. I found a roll end on ebay for £28 inc delivery. It's indestructible, it has a solid core unlike the foam-filled home grade stuff. I put it down before the toilet and pedestal, it should last as long as they do. It's smooth but has embedded sparkly crystals of grit in it, it's impossible to slip however wet your feet are so totally safe. I won't buy home grade stuff ever again.