DIY novice, help needed! Cement board and vinyl click flooring install in bathroom.

[MrBosch]

Hi everyone, novice diyer here. Just scoping out whether I can do a job myself, also had conflicting advice from trades so wanted to ask the excellent hive brain on this forum!

Currently renovating the bathroom. Tiling all done and shower tray and bath installed.

I want to install vinyl click flooring. It's an old house so has traditional 20mm floorboards. My plan is to install a 6mm cement board subfloor. But I have a few questions I need help with.

Plumber says it needs a flexible rapid set tile adhesive (S1) first and then screw in the cement board with 25mm screws.

Had a flooring chap round this eve for the rest of the house and asked him to quote me anyway for the bathroom flooring with labour only. He said no need for tile adhesive with vinyl click and to screw it in directly to the floor. I've installed laminate myself easily enough over floorboards and only ever needed a floating woodfibre underlay so it made some sense to me.

So what I need to know is who is right?

If I did do this myself, assuming I didn't need rapid set, I've read the Turbo Gold wood screws are good for cement board. Would that be a 3.5 20mm size? If not which screws would you recommend?

Thanks in advance.

 

[Deleted member 174758]

I've read the Turbo Gold wood screws are good for cement board. Would that be a 3.5 20mm size? If not which screws would you recommend?

Pretty much any reasonable screw will work with cement board, but it is probably better to pre-pilot and countersink the holes to guarantee the screw heads being flush.

I always use larger screws, though. I think 3.5mm screws have more marginal holding power.

For example I am currently framing and boarding out some new toilets in an office refurb. Many of the lower walls are being boarded with 12mm cement fibre board to take tiling. I'm using drywall screws, partly because they are going onto a mixture of timber and (mainly) metal framing, but also because drywall screws are dirt cheap, even the self-drilling ones we have for the MF. Drywall screws have the same size heads (approximately) as 4.0 to 4.5mm woodscrews and give better pull out resistance

 

[con1_uk]

So are cement boards OK on the floor under the vinyl click please? My boards are a little flexible with foam type stuff on one side and the harder surface on the other.

Ta

 

[Odds]

Cement boards are fine. Is your bathroom above the kitchen?
You shouldn't need to glue down vinyl click boards but check the label before fitting.
The type you describe don't require adhesive.

 

[con1_uk]

Hi, yes bathroom is above the kitchen, currently the bathroom floor is chipboard which I need to remove all the old grout from, hoping to use the cement boards instead of 6mm ply to level it and provide a sound platform for the click flooring.