Bathroom floor - to ply or not to ply

[Mug-o-Latte]

Folks,

As part of the work to fit a new bathroom, I've ripped up most of the tongue and groove chipboard flooring which I was going to replace with new stuff. Eventually I want to put down a waterproof laminate like Karndean, which requires a ply base.

Do I need to replace the chipboard flooring and put the ply over it, or can I remove all the remaining chipboard and just put the ply directly onto the joists? This way I would end up with a laminate floor a similar height to the room next door.

Any thoughts?
MOL.

 

[masona]

can I remove all the remaining chipboard and just put the ply directly onto the joists? This way I would end up with a laminate floor a similar height to the room next door.

Yes that's the best way to go and make sure you use exterior plywood and at least 18mm or 3/4" thickness and with non-rust screws approx every 9"

 

[Mug-o-Latte]

Masona,

Thanks for the response. I've heard people talk about marine ply. Is this the same as exterior ply?

MOL.

 

[masona]

Well they use marine ply on boat ! We have a boatman chap here on this forum who might be able advise you further.

The exterior plywood have waterproof glue between layer of ply sheets.

 

[2scoops0406]

I am prefectly willing to admit I'm wrong here, but I thought marine ply, and exterior ply were the same.

 

[masona]

No, you're not wrong, they both use difference bonding materials.

Exterior plywood use waterproof glue which is graded as WBP (Weather and Boil Proof)

Marine plywood is also waterproof, I think they use epoxy resin glue but I'm not sure.