Fixing Backer Boards to solid walls with plugs and screws

[Institute FUF]

Hi all - am a new member, a DIYer largely without any particular skills.

Can I start by asking a question - I want to fix 6mm No More Ply backer boards (1200 x 600mm) to a solid shower wall using screws and plugs before tiling. Can anyone please advise me on: -
(a) At what centres should I fix screws?
(b) What size/length screw should I use?
(c) Which wall plugs should I use?
I'd prefer to avoid reliance exclusively on adhesive for fixing the backer boards as this will simply add to the weight that the slightly dodgy plaster is being asked to bear in addition to the tile weight - hence preferred method of using screws and plugs.
Advice welcome and will be gratefully received!

 

[Dan]

Welcome to tilersforums.com | Tile Forums | Tiling Forum!

Welcome to tilersforums.com Institute FUF. Thanks for introducing yourself.

 

[Gazzer]

I would deal with the " dodgy" plaster before going any further.

 

[Institute FUF]

Thanks for that but I probably used the wrong expression - it's not dodgy in the sense that it's loose or blown, it's just a tad uneven with one or two small areas of missing skim following removal of the previous tiled finish.
The main reason I am using the backer boards is to build up the wall to ensure it allows the tiles to overhang an upright tiling lip on the top of the shower basin - long story - I know I should have fitted the latter such that the existing plaster allowed tiling over the lip - i.e. by cutting away the surface of the wall before positioning the shower tray - but it's an alcove, a very tight fit and a very heavy shower - after much struggling, and cutting away of the wall I had to accept that the lip would be slightly proud of the plaster on one side (the other 2 sides are perfect) - but 6mm backer board would create exactly the right surface configuration finish above the shower tray for tiling over the lip. So if you could advise on centres, screw sizes etcetera it would be much appreciated.

 

[kilty55]

hello,i would remove the dodgy plaster 1st,cant you dot and dab plaster board onto the solid wall after this?

 

[mikethetile]

:welcome:I would remove the plaster on the other walls too, what tiles are you fixing

 

[united]

:welcome: to the forum

I would also use plaster board and dot and dab on to the brickwork

 

[Institute FUF]

Many thanks to you all but I now regret using the expression dodgy - sorry - it's just a little uneven from the process of removing the previous tiles. I already have the tile backer boards for the wall in question and my main purpose in using them is to add that extra 6mm to the surface of the wall such that it will ensure the tiles, when applied, nicely overhang the upright tiling lip on the very heavy and difficult to install shower tray below. So if you could help with screw sizes and centres for fixing the backer boards it would be very much appreciated. I am using a ceramic tile sized 230mm x 400mm.

 

[DHTiling]

:welcome::welcome::welcome:

 

[suave]

:welcome:

 

[Diamond Pool Finishers]

hi :welcome:to the forum

 

[The Legend; Phil Hobson RIP]

:welcome:

 

[White Room]

Hi and welcome

No more ply say that you can fix 6mm boards on existing surfaces with there adhesive

 

[Institute FUF]

Thanks for that - I'll acquire some of their adhesive but they also suggest that some mechanical fixing - i.e. plugs/screws- may also be necessary but don't elaborate any further. I'd like to do a belt and braces job so wish to use mechanical fixings as well as adhesive - can you recommend a screw/plug size and centres for fixing?