ply v backerboard on floors

[neild13]

Hi there,

It's my first post so please be gentle with me!

I've decided to overlay floorboards in my bathroom in prep for floor tiling (I've ruled out replacing the floorboards for reasons I don't want to bore you with). I've read loads of posts on here and I think I get what's required for overlaying with 12mm ply. But some people do it with 6mm hardiebacker boards. Can these be laid dry like ply or is it essential to have adhesive underneath before screwing them down? If so, what thickness of adhesive? Just trying to work out how many mm less thickness there'd be if backer boards were used.

Also, I guess I'll have to leave a gap between tiles and skirting whatever I overlay with. How big should this gap be and how is it best to finish it off? Will I have to put a wood covering strip along the bottom of the skirting (like I did with laminate flooring) or could it be filled with sealant? I'm guessing grout would be out due to the amount of movement.

Thanks

Neil

 

[iwaters]

Cement boards must be bedded on adhesive, this it of ill any voids and give a solid base, otherwise the board and tiles can crack. Hardibacker is recommended to be installed using a 1/4" notched trowel so you wont be adding much in the way of thickness from the addy, especially after it is screwed down.

It will be lower that using 12mm ply. Have you check how thick the floorboards are and the size and spacing of the joists?

You will want to have a gap of around 4mm from the wall for both the board and the tiles. You can fill the gap with grout and then run a bead of caulk or silicone to finish it off but I prefer to pull the skirting off run the tiles close to the wall and install new skirting over the top of the tile. Looks much better and only adds a few quid and a couple of hours to the job.

 

[tpt]

no more ply is laid on a solvented adhesive like no more nails, and screwed down too. This seems to work very well and is less work than bedding with tile adhesive.
see here
http://www.nomoreply.net/overboarding TIMBER.htm

 

[neild13]

Thanks, iwaters & tpt, for all your advice. We're going to go with no more ply provided there's a stockist nearby.

Regards

Neil

 

[tpt]

i'm being a bit naughty in terms of forum rules here, by all means get it locally if you can, but if you can't i can supply it to you for £7.92 each inc vat, as long as you buy more than 10 (£8.49 if your more than 5).

Delivery is £25 inc to anglesey, this can also include your adhesives etc if you wish.

if you email no more ply, they will tell you your nearest stockist.