There are lots of different ways to install mirrors, in this post I’m going to focus on glue-back application, which like it sounds, is where glue is applied to the back of a mirror to hold it to the wall.
Choosing the right silicone
Always use a neutral cure silicone when gluing mirrors. Acidic cure silicone will degrade the back of your mirror and lead to black spots over time. If you’re not sure, just ask your local hardware store to point out the right type.
What’s the difference between wet and non-wet areas?
Wet areas are slippery – so there’s a higher risk of someone falling into the mirror in your bathroom or laundry, compared to say your lounge room.This is why mirrors in wet areas need to be installed in a different way to those in non-wet areas. The mirror in a wet area needs to be installed properly so that if it breaks, it stays together and doesn’t break into shards that could cause serious injury.
How to install a mirror safely.
When I install mirrors in a non-wet area wall I use blobs of silicone, roughly the size of a fifty cent coin and as thick my thumb, the blobs should be spaced approximately 200mm apart across the full height and width of the mirror. Using blobs in this way creates more suction, which holds the mirror in place until the silicone goes off (or sets), usually making mirror tape unnecessary.
How to apply glue for a non-wet area job
If you apply the silicone in the way I describe above, it should hold the mirror to the wall, however, care must be taken to support the bottom edge until the silicone has set otherwise it will start sliding down the wall. If there is a solid object below the mirror, like a bench, use a piece of cardboard between the mirror and the object until the silicone sets. If there is nothing to rest it on, use some temporary props like timber to hold it in place. Neutral cure silicone usually takes 24 hours to fully cure (or set), always check your tube for recommended curing times.I
If you’re worried about the mirror falling of the wall while the silicone cures, there are double sided tapes you can use in conjunction with silicone. Never use this stuff on it’s own – it’s only meant to hold the mirror until the silicone sets. Make sure the tape is suitable for mirrors.
Never glue a mirror to the ceiling (I wont ask why you want a mirror on your ceiling, but its a very dangerous idea). There are safe ways to fix mirrors to a ceiling but this is something best left to a competent professional glazier.
Mirrors in a wet area
According to the Australian Standards all glass that is to be used in wet areas must be Grade A safety glass, this includes mirrors. Only mirrors with a full backing of vinyl or similar are classed as Grade A but gluing vinyl does not work, the silicone does not adhere to vinyl properly and so this only leaves mechanical fixings like clips or dome covered screws, however there is a way around this.
It involves gluing the mirror in a special way were instead of blobs you use lines. The technique accepted by the Australian Standards is to use lines of neutral cure silicone, as follows:
- Starting 50mm from one side of the mirror run a 5mm thick continuous bead vertically from the top of the mirror to the bottom.
- Continue this every 70mm till you reach the other side of the mirror.
How to apply glue for wet area jobs
From here, to install the mirror, use the same process as described above. The lines of silicone, when dry act as a complete backing that hold the mirror together if it breaks.