i wonder if anyone has words of wisdom about how to mount a large
mirror in the bathroom. In my case the mirror is 2200mm x 600mm and
6mm thick and weighs about 25 kg. It will be vertical (almost from
floor to ceiling). It has 4 holes along each vertical edge for screw
mounting to the wall. The wall is traditional plasterd blockwork
(internal).

The wall is not perfectly even. Obvioulsy I want the mirror to be
flat but i don't want it to have large hollows behind so that it could
bend/break if someone leaned on it. It has a safety backing so that
it does not fall apart if it breaks but it is not toughened.

My idea was to first mark, drill and plug the eight screw holes. Then
I would put blobs of sealant on the wall dotted over the surface at,
say, 150mm centres. Then I'd mount the mirror screwing to the wall
but not too tightly. This would squash up the sealant blobs which
are sandwiched between the wall and the mirror.. Once the sealant
has hardened the mirror would be flat and well supported.

I am worried the sealant might damage the reflective coating on the
back of the mirror so I plan to cover each 'blob' with a bit of vapour
barrier plastic to isolate it from the mirror. This would also make
removal easier.

Any comments or suggestions would be welcome.

Robert