To ply or not to ply.

[cox377]

Hello guys,

looking for a bit of advice. My current bathroom floor is floor boards. I've read in some places that you can tile striaght onto floorboard as there is no deflection and by using BAL Fastflex or Ardex 7001 timber systems along with an appropriate flexible grout.

The bathroom is quite small and the beams below are supported by steels so hopefully minimum deflection.

I'm looking to minimize step height.

Would it just be better to pull up the old boards and lay 18mm ply? or is it 18mm ply ontop of boards?

Thanks in advance

CoXen

 

[PrenticeBoyofDerry]

Best method would be to lay 12mm WBP ply over top of existing floor.

 

[JohnD]

Would it just be better to pull up the old boards and lay 18mm ply?

yes

 

[Richard C]

Ask mods to transfer this to Tiling, you’ll do much better than in Building.

I'd generally go with JohnD but there can be other options, depending on local circumstances. But I'm off to have me dinner & a few glasses of decent grape right now so I’ll have a look back later in more detail

 

[TrumpersUnited]

Hope you enjoyed the vino tinto Richard?

I wouldn't risk tiling direct onto floorboards.

I would personally use 6mm hardibacker on top of the floorboards. Then use a good SPF adhesive.

 

[Richard C]

I wouldn’t tile straight onto floor boards either. As said, I normally prefer to replace the floor but it much depends on condition & individual circumstances. You can either overboard with 12mm WBP ply (seal the back & edegs with SBR) if the threshold height is not a problem; or if the tile area is very small & the joists are up to it, you could use 6mm HardiBacker but, personally, I would go for the thicker 500 (12mm) board on larger areas & this won’t give you any advantage over using 12mm ply. You can then come down on the addy spec & use either Rapidset flexible or Single part flexible.

Vino was excellent, so good in fact I completely forgot about this thread.