Wall-mounting 8x4 mirrors for fitness studio

[blackworx]

Hi folks,

Having a bit of a crisis of confidence with a mirror wall. Never worked with huge sheet glass before and I'm starting to think I might've bitten off more than I can chew. I wonder if anyone in the know can tell me it'll (probably) be alright, or if not point me in the right direction?

The plan is to have four 4mm 8x4 mirrors, trimmed a few inches short of the full 8', wall-mounted to cover the entire length of one wall (brick/plaster). The wall itself is nowhere near flat, so I was planning to glue the mirrors to 12mm ply and mount the ply to 2x1 battens running along the length of the wall top and bottom, then fill the gap between the wall and the ply with polystyrene.

I've got as far as doing a test-mount with the plywood on its own. After fixing the battens I've put threaded inserts in them, and used M6 machine screws (12 per sheet - 6 top, 6 bottom) to mount the ply. It's all perfectly sturdy, but now I've got to the stage where I'm ready to order the mirrors and polystyrene backfill, I'm looking at the boards and noticing every slight warp and bend, and starting to worry that the ply might shatter the mirrors .

The way I see it there are 3 possibilities:
1) I'm worrying over nothing
2) I need to get thicker ply and/or thicker mirrors
3) I should cut the possibility of a million years bad luck and shell out for acrylic mirrors.

Thanks for reading and apologies for such a long post!

 

[dextrous]

Interesting scenario. Have you tried talking to the glaziers about your intentions? They may well know how it's done, or may have contacts who can advise - it's not unusual (I'm thinking "dance studios" here). Personally, relying on the mirror to self support itself with glue worries me - will the mirror paint not unpeel itself with the weight of the glass?

 

[dave2]

I had a wall about 15m long and 2.4 high covered entirely. For appearance sake I had the mirros cut so they were 2.4x600 and they are fixed to the plaster wall with the mirror fix adhesive. The glaziers fitted for me an all is fine.
I wanted a copule or large mirrors 1.2x1.2 fitted, so ordered the mirrors and mirror adhesive and did the fixing myself.
It is a must that you use the correct adhesive, as if you use general no nails type, you will damage the back of the mirror and it will show through black.
What I believe you have to be careful of with your project is that any light film of dust on the plywood will prevent correct bonding and the mirror could come away.
I did see this happen where someone had stuck foamex sheets over a mix of plasterboard, ply and plastered walls. It stuck to the plaster walls, but a couple of weeks after, it just came away from the ply and plasterboard. Inspection of the sdhesive showed there was a film of dusts and it could be pulled off the plasterboard in places, without even damaging the board.
Get the professionals to fix it.

 

[blackworx]

Cheers for responses.

Can't have them fixed directly to the wall, as they need to be removable. Also the wall isn't even close to being flat and I know the plaster-work is dodgy so although I completely trust mirror adhesive, I wouldn't trust the skim not to come away.

So, in short, there's no way even the pros could fit glass mirrors to the wall without getting it replastered.

I've finished fitting the panels and I've decided to go for 6mm acrylic mirrors. It's only a couple of hundred quid more than glass and there's no danger of them cracking with a slight bend in the panels.

 

[dave2]

Battens screwed to wall, plasterboard, seal plasterbord, mirror adhesive and morrors, with some mirror fixing screws into batten just in case.
Acrylic mirror compared to glass. No thank you, you never get a true reflection.
Get the glass mirror toughened. It will take a fair old bump.