Tiling on suspended timber floor

[reeshar]

I'm looking for some advice, I'm planning to tile the hall floor of my 1st floor flat (approx. 8m²), the existing floorboards are a bit knackered as it's an old (1870's) building. I was planning to lift and remove the existing floorboards, brace the joists with 2x8 at regular centres and at the joints between the new ply flooring to be laid, then overboard with 24mm ply which I was going to seal with Zinserr Bullseye to limit moisture/vapour ingress. This would bring me level with the adjoining rooms which have sanded floors, so with tiles and adhesive I'd have a 10-12mm step which I can easily hide with a threshold. I'm looking at using fairly small tiles (although of a suitable thickness for flooring) so I was also hoping that might help limit any potential cracking issues.

I've been reading around and it seems like tiling on suspended floors can be tricky as you don't want deflection and tiles or grout lines cracking. What's the consensus, would this be suitably stiff to resist any movement? Alternatively I was thinking I could use 18mm ply and 6mm backerboards. Any advice much appreciated.

 

[Dumbo]

I would go with option 2 .

 

[Bill]

This does not read like a 'new' type of suspended floor, it is more like a reboard onto fixed joists. There are numerous methods to use that wouldn't need the use of 24mm ply.

 

[reeshar]

Thanks for the replies guys.

Tom, what would you recommend? Maybe I didn't use the correct decription, yeah this taking out the existing floor down to the bare joists and relaying.

JCR, what's the reason to go for option 2?

Another question, what about using moisture resistant chipboard and ditra, as mentioned in another post on the forum, would that be a good option here? The joists are 450mm centres (well approximately, don't think tape measures or spirit levels seem to have existed in the 1870s!).

 

[Stu Lilley]

Remove the floor boards and fix 22mm no more ply cement board direct to joist and tile... simples

 

[reeshar]

Thanks Stu, the cement board sounds ideal. I'll go for that and post back how I've got on, it'll be a couple of months as I've got a lot of other work to do before I start the floor but it might be useful for someone else coming across this post in future.

 

[Stu Lilley]

Thanks Stu, the cement board sounds ideal. I'll go for that and post back how I've got on, it'll be a couple of months as I've got a lot of other work to do before I start the floor but it might be useful for someone else coming across this post in future.

Hope all goes well...kind regards stu

 

[Time's Ran Out]

22mm no more ply direct to joists and tile!
What guarantee do they offer?

 

[hmtiling]

22mm no more ply direct to joists and tile!
What guarantee do they offer?

I believe it's a lifetime guarantee