We have 4 door mounted mirrors which are found on the bathroom cabinets above the sinks. Each mirror is fastened to the door face using a mastic which isn't visible. That is until one falls off. That's exactly what happened back in June of 2009 when Jeannie innocently pulled on the handle to open the cabinet. The entire mirror simply let go and proceeded to head straight for the sink. Luckily she was able to catch it, brake the fall and avoid it from smashing in the sink.

Mirror falls completely off cabinet door.

The mirror has a plastic coating on its back which is designed to hold it together if it should break. The idea is to avoid shards of glass from coming off and inflicting personal injury. Since the mirror never broke, I have no way of commenting on how well the plastic would have worked. I do know if the mirror broke and hinged it could have exposed a razor sharp edge and inflicted a serious cut. Luckily this didn't happen and having an unbroken mirror made the repair easier.

The plastic backing is slippery which means certain mastic compounds won't adhere to it properly. On this mirror silicone was used which obviously wasn't a good choice. Silicone comes in zillions of grades so it's anyone's guess what was used. My guess is something quick, easy and cheap was used to just get the job done. Another consideration is the oil used in the wood stain which tends not to be a good bonding surface. Just about any mastic supplier will tell you to remove dirt, oil and grease from the surface before applying their product.

To effect repairs, I thoroughly cleaned everything and sanded the wood at the bonding surfaces. My choice for a mastic was black Sikaflex 227. Given the bonding surfaces I had no idea how this would hold up. It turned out to be a strong and reliable bond. The mirror has stayed in place since June of 2009. Oddly so have the other three mirrors.

If you wanted to go the distance and do the job correctly the other three mirrors should be removed and re-bonded with Sikaflex 227. You'd need some fine piano wire, care and patience to break the existing bonds. I haven't undertaken this project as of late.

This is one of those nuisance failures that just shouldn't happen but did nonetheless. Please do inspect your mirrors and re-bond them as required. We got very lucky when ours let go. Another falling mirror episode may not return the same good luck.

If anyone else has had this problem and used something to re-bond please feel free to post your solution here.
Evolve and simplify!
Scott Bridgman, Why not join and post your own comments??
scott@muniac.com (email me)