Movement in bath and wall - should i be concerned?

[YADT]

I'm in the process of doing our main bathroom. We have had a shower added to the bath (i.e you stand up in the bath and shower rather than a seperate shower cube) and i've noticed that after standing in the bath to get the existing tiles and Silicon off, the bath is moving and the wall is flexing when pressure is applied to it down the long side of the bath.

The wall down this long side is an internal studded wall, probably using a metal frame if its the same as other walls in the house. As has been the case with every other diy job i've done in my house, nothing is ever straight forward because of the crappy build quality.

Anyway, having looked at the existing fixing of the bath tonight, there are two pieces of wood in the wall which a bracket coming off the underside of the bath is nailed to. However the two bits of wood are just being held inside the studded wall by the nail - they arent actually fastened to the wall.

I'm going to build a timber frame around the bath as best i can to help support the bath, plus i need something to fasten the bath panel i'm going to make to, so the frame will serve two purposes.

Given that the wall is flexing in the middle just above the bath by around 2-3mm when i lean against it, is that something i also need to worry about regarding the seal around the bath?

I dont mind ripping out the plasterboard, strengthening the frame and re-boarding if that it the best option. If i reboard, should is use plasterboard or go with a cement board?

I've seen in other posts people talking about tanking which i understand is some waterproofing thingy - still yet to read up on it though. Since i'm changing the use of the bath into a shower, should i be doing that? I'd rather not have to rip out all the walls, and we are not tiling the wall on the other side of the bathroom from the bath - thats just being painted for now.

If tanking is going too far, should i do some other waterproofing stuff just around the bath?

Thanks
Ian

 

[faithhealer]

hi yadt Iusually fasten a baton to the wall before the bath is put in, silicon on the baton and between bath and wall. doesn't move after that

 

[White Room]

I take it there is a 50mm metal frame/studwork which is pretty weak...........

If your going to do a wood frame for the bath fix it to the stud wall thru to the metal studs which should hold it together.

I would tank the plasterboard

 

[YADT]

Thanks for the replies.

The air-gap between the plasterboard looked to be around 40mm but it could have been 50mm. So far no one thinks i need to rip down the wall, strenghten the frame and reboard it so at least thats one job i havent got to worry about

I want to put this frame in around the bath without having to remove the bath (me and plumbing/pipes dont get on!) so i might have trouble going with faithealers suggestion.

 

[faithhealer]

going to be a squeeze trying to get under the bath.

 

[doug boardley]

I hate tiling onto metal studs, they're usually 600 centres, waffy as hell because builder/framers haven't put noggins in them. If this is the case YADT I'd be inclined to expose the metal framing and put in some noggins/bracers

 

[Steve H]

Hi Ian,

Like me, you have received loads of good advice above. I completed a course at NETT in Feb this year, since then I have dabbled in a couple of friends bathrooms (that doesn't sound good). This summer I did a similar job to what you are contemplating, a complete refit of my bathroom. With the help of the guys on this forum, I finished the job about 2 weeks ago. Here are a few phots to let you see my progress. I know that I have made mistakes, but I am learning to live with them. I deliberately chose not to tank, probably my biggest mistake, hopefully not one that will bite me later. Hope the phots give you inspiration, or a laugh!
Good luck!

Steve

 

[YADT]

I hate tiling onto metal studs, they're usually 600 centres, waffy as hell because builder/framers haven't put noggins in them. If this is the case YADT I'd be inclined to expose the metal framing and put in some noggins/bracers

Well the plasterboard came down over the weekend. The studs were at aound 900mm centres, basically they were set to the width of the plasterboard, and there was just one noggin between each one at around head height so this totally explains the flexibility in the wall.

The plasterboard was 16mm thick and the metal stud frame was 40mm depth (whitebeam suggested they were 50mm - no such luck). I'm going to take out the metal noggins and brace either side of the metals frame that is left with some 44mmx70mm PAR timber along with some additional lengths to create something around 300mm centres, and then put my own timber noggins in as required. The wall is then going to be boarded with cement board.

The wall i've taken down didnt have any insulation material (unlike the photos from SteveH) and i dont reckon its worth putting any in because the other two inner walls wont have any either, so it hardly seem worth it.

The bath is now coming out for two main reasons, 1) so i can the rest of the plasterboard out & the cement board in behind the bath and 2) so i can fit new taps & properly fit the wooden frame i mentioned originally.

I hate plumbing because something always goes wrong, but i hate doing a bad job even more :smilewinkgrin:

Will post photos like Steve did when its all done.

Ian

 

[faithhealer]

Fit full bore valves all over the place, then if something goes wrong you can isolate the problem without turning the water off for the whole house

 

[YADT]

Thanks faithealer

The loo and the sink already have them, but i went out and bought a couple of 22mm ones for the bath the other day once i had decided it was coming out. I'm also going to put some flexible pipe between valves and taps but currently having trouble finding a simple solution to that without having a short length of copper tube between the valve and the flexible pipe. What i mean is the valves i got are compression fitting both endv, and the flex pipe i had in mind is compression one end and 3/4 bsp the other.

will probably go to local plumbers merchants and tell em what i want to do and see what they suggest.

 

[faithhealer]

The flexis you want are available in any plumbers or diy store, Are your bath valves full bore or thyour bath will take ages to fill

 

[YADT]

TBH i dont know if they are full bore or not. I got them from Homebase the other day when i was in there looking for some paint. Didnt actually go in there for valves but when i got home and found that places like screwfix were selling them for around £3 each and i'd just paid about £8 each i decided they were going back anyway and i'll get some from a plumber stores.

At least i know what to ask for now, thanks