Fixing wooden floors

[steve_c]

Hi everyone,

I need a bit of advice please with a new bathroon tiling job. The majority of the existing boards have been replaced by the builder with 18mm green chipboard nailed once or twice in places. Where the boards are ok they have been left but still abit loose. I've just bought 6mm no more ply to go over but not sure how to go about making good the current chipboard and wooden boards first. What centres, and what size screws etc do I need? Also concearned about pipes running underneath in joists? Any advice appreciated.

Thanks,

Steve

 

[grumpygrouter]

All chipboard should be screwed to the joists at no more than 300mm centres. When you ply over the top use at least 15mm WBP or marine ply (unless you really are tight for room, in which case consider something like Hardibacker backer board, or is the "no more ply a similar thing?) This should then be screwed to the chipboard at around 150mm centres. Screw length depends on your chosen thickness of ply, i.e if you have 18mm ply into 18mm chipboard use 30mm screws. This won't penetrate through the chipboard then. I always pilot drill my ply to the shank width of the screw so that you are only screwing into your chipboard. This gives a clamping effect and lessens the likelyhood of your ply "lifting" and leaving a void underneath - not good for floor tiling!

 

[DHTiling]

As grumpy says screw down the existing floor well...prime with bal apd neat..allow to dry...then put your no more ply backer boards down with flexi--adhesive and screw down every 300mm or so....then tile on this............dave...

 

[NickH]

If there is any doubt about pipes then you should lift up enough boards to be able to get your arm under and check EVERY joist that you are going to screw into. 90% of the time you could get away without checking but the first time you hit a pipe you'll be SOOOO sorry you didn't check. This is coming from someone who spent two hours yesterday repairing the flow AND return pipes from a boiler. Two pipes with one screw takes skill !
Careless, careless, careless.

 

[DHTiling]

ha!..two pipes in one go...now that "is" bad luck.....lol lol.......dave...

 

[steve_c]

Thanks for the replies.

I got some 40cm chipboard screws from b and cute on my way home tonight.
I think i'll take afew boards up and have a good nosy under there first. Sound advice!
I got 25cm screws for the 6 mm no more ply. I think it's the same stuff as backer board, just different name.

Thanks,

Steve

 

[petergft]

If you want to limit the amount of floorboards to remove, to check for pipes, try using a mirror and shine a torch light onto it to illuminate under the floorboards!
Pete