Subfloor build up on timber joists.....

[117ws]

Hi all,

After a bit of advice on subfloor build up if those in the know could help out?

Am in the process of renovating my bathroom in my Victorian terrace - approx 8m2, floorboards have been lifted for fist fix plumbing (not re fixing as they're in a state)

My thoughts on subfloor for laying wood effect tiles is as follows:

18 or 22mm ply fixed to joists (inc noggins)
6mm hardibacker on adhesive
Electric UFH
SLC
Adhesive
Tiles

Is this recommended? is 22mm ply by far superior? (Original boards are 20mm)

Or is ply/wedi better?

I have been recommended to use tops construction board which is only 20mm and no tilebacker needed? - unsure on strength in comparison?

All help greatly appreciated!

 

[Qwerty]

Personally I would go-

22mm ply fixed to joists (inc noggins)
6mm Insulation boards on adhesive
Warmup DCM Pro Electric UFH
Adhesive
Tiles

 

[117ws]

Hiya,

Thanks for the reply much appreciated!

Why the insulation boards? For heat distribution? I assume the compress at all? (I’ll be having a freestanding bath so wanted as solid a floor as possible)

I’ll hsve a look into the insulation boards, any recommendations on brand?

 

[Qwerty]

Heat efficiency primarily. IMO they are easier to work with and result in faster warm up times.

 

[117ws]

Any opinion on using 22mm structural MR chipboard as opposed to ply?

I was sold on the ply idea initially but noticing that the chipboard is down as structural and the ply wasn’t it got me thinking.....mainly as I will be installing a cast iron bath.. any thoughts?

 

[117ws]

Anyone got any opinion on 22mm mr t&g chipboard strength?

 

[Time's Ran Out]

I wouldn’t consider chipboard anywhere near moisture!

 

[117ws]

I was the same, however in real terms if the shower area is tanked and the chipboard elsewhere over overlaid with insulation board and slc how much moisture is it going get?

Also the t&g chipboard noted as load bearing where as the ply I was looking at isn’t...but I know what you’re saying...