Tiling on bowed/warped T&G

[Price]

Hi,

All advice welcome please.

a DIY job, I need to tile my bathroom floor. It currently has T&G floorboards which were carpeted over. I lifted the carpet when we moved in and the floorboards have warped resulting in raised (long) edges. Looking at it another way, they dip in the middle along the length of the floorboard.

If I WPB over them and then tile, does anyone know if I am likely to get problems - or should I cut them as close to the wall as I can and replace with new boards or WPB before tiling ?

[Oli]

Personally I'd cut the boards back to the walls and replace with 25mm WBP Ply, you can then add extra noggins as required at the same time.

[Frosty]

Yup, as the song says..."rip it up and start again!!"

Same as Oli says, 25mm wbp with extra noggins where required.

[david campbell]

ditto,don't think theres any cheaper or quicker method that will leave you a good surface to work from

[whitebeam]

The floor boards sound they are not good a quaility, as the other guys have said.

[rob]

Yep agree, do it once and do it right. Might take a little longer but at least you wont have possible grout cracking problems due to movement later down the track!

[Price]

Thanks all for the advice - looks like it is out with old t&g and in with the wpb. Challenge now is to cut the old ones as close to the (block) walls as I can. Good stuff - thanks>

[pjc]

you could make sure the floorboards are well screwed down and overboard with PCI 10mm backer board the undulations being taken up with the adhesive under the backer board :Pete

[rob]

you could make sure the floorboards are well screwed down and overboard with PCI 10mm backer board the undulations being taken up with the adhesive under the backer board :Pete

Might lift the level of the floor too much!

[Price]

Existing boards are 18-20mm. Does anyone know if 18mm WPB would suffice as I have some left from a different project. Joists are at 400mm centres.

[Frosty]

Not ideal, but as it's for you and not a paying customer i'd say at 400c/c screwed down every 150mm you'd probably be ok.
Make sure a flexible ady is used.

[Price]

Slightly confused over nggin spacing.

If I go for screwing 18mm wpb down every 150mm along the joists do I also need to fit noggins across the joists so that the noggins are 150mm apart (centres). That would allow me to screw along the noggins every 150mm as well so I can see it makes sense - just sounds like a lot of noggins.

Up for doing a thorough job so don't mind that many noggins - just want to make sure before going too far.

Advice welcome please.

[Sir Ramic]

Better to over do things than skimp.

[Dave]

Slightly confused over nggin spacing.

If I go for screwing 18mm wpb down every 150mm along the joists do I also need to fit noggins across the joists so that the noggins are 150mm apart (centres). That would allow me to screw along the noggins every 150mm as well so I can see it makes sense - just sounds like a lot of noggins.

Up for doing a thorough job so don't mind that many noggins - just want to make sure before going too far.

Advice welcome please.

300mm spacing is BS standard...overboarding an existing substrate requires closer fixings but not direct onto joists....22mm ply would be my option and then keraquick with latex plus.....

[Price]

Cheers for the advice. I'm going straight onto the joists and not over the existing boards - they are too far gone.

So the upshot is I put a noggin in every 300 mm if I then screw 22mm ply on top, with the screws going in every 300 mm.

As I said earlier - all advice welcome - thank you.

[pjc]

Might lift the level of the floor too much!

tile on the floorboards then, you will be lifting the tiles up instead