concealed shower mixer valve

[panhandle]

This is my first posting so I hope that I can make clear my problem.
The breeze-block wall in which I wish to install the mixer valve is 120mm deep including plaster(closest estimate).

How deep a recess would it be reasonable to attempt even if carefully cut by hand? I assume that there would also be fixings to screw into the remaining (thickness of) back wall.[/b]

 

[LeedsPlumber]

I wouldn't be chasing out much more than an inch or 2, can you not build a stud wall to conceal the shower valve, 120mm sounds allot for a concealed shower (the part that goes in the wall anyway) and i don't think it would be a good idea to chase it in to the wall completely.

What are your plans for running the hot, cold and shower head pipework? recess them aswell? there may not be much wall left by the time you have finished. Think you may be better changing to a surface mounted shower.

 

[Richard C]

This is a common problem with concealed mixer valves some of which demand huge recesses & it catches many out. As LeedsPlumber points out, you don’t want to be chasing out too much of the block wall; if you’re not careful there won’t be much of it left to mount the valve onto; I’ve even know folks break through the into the cavity which is the last thing you want. The easiest way is to recess ½ the depth (max around 50mm including plaster) & batten out to create a false stud wall to take the other half of the valve & all the pipework. I sometimes take the stud across the whole wall so it’s not obvious in the finished bathroom. Line the stud with a waterproof tile backer board in the shower area.

Or pick a surface mounted valve with exposed pipework.

 

[panhandle]

Re- concealed shower mixer valve. M. tks Leeds Plumber and Richard for all the useful gen; the method of using a shallow stud wall could be the solution.

One point to note - it is the wall that is 120mm thick/deep (an internal wall and not a cavity wall) and not a 120mm recess that is needed. My info tells me that the recesses vary commonly between 50mm and 80+mm. I suppose the crucial question is how much of the remaining breeze block wall do I need to screw the valve onto. If there was still 60mm of back wall remaining would it be worth a go? Waddya say? [/u]

 

[seco services]

yes cause it is by the time you have the pipes in and clipped and the mixer bracket it'll be fine.

 

[denso13]

Yep could be worth a go especially if it's breeze block as you can virtually scrape it out.

BTW the fixings are not always in the rear of the valve but on a bracket attached to it so you should be fixing into the full wall thickness to the side of the valve.

 

[JohnD]

after chasing a big hole into a wall I like to refill it using sand and cement mortar (wet the hole first) as this is strong and dense compared to plaster or filler. wrap the mixer so you can lift it out in future.

be aware though that shower mixers go wrong, so you will come to regret building it inro the wall and tiling it. I always prefer a surface mount for that reason.,

i am a householder not a pro.

 

[seco services]

browning is better for backfilling.

 

[Richard C]

Sounds obvious but don't forget to deduct the thickness of the tiles & grout; & some of the pressed faceplates can be 10mm deep!