How to tell tempered glass from polycarbonate

[Kent Adams]

I bought a couple of these doors: http://www.homedepot.com/p/Masonite-...7315/100075801 which I'm finishing with Waterlox Marine. The borg's website says they have tempered glass, but I can't tell by the "tap" test that it is in fact glass.

Because I'm using Waterlox Marine, which has mineral spirits in it, I'm concerned about the "glass" with the overflow of Waterlox on it. If its actually polycarbonate, I've read that MS can cloud it up. Is there a way I can test to make sure it's actually glass, other than trying to scratch it?

[John Aperahama]

Tempered glass is expected to have a stamping (etching) on it during manufacture. I personally have always thought that these doors from HD are not tempered.
Probably not poly tho.

[Kent Adams]

Tempered glass is expected to have a stamping (etching) on it during manufacture. I personally have always thought that these doors from HD are not tempered.
Probably not poly tho.

It does have a stamping on it, but I can't read it for the life of me.

[Wade Lippman]

If it does cloud up with MS you can take them back.

[Jason Beam]

Take one out and look at the edge ... AFAIK tempered glass is green on the edge.

[Jamie Buxton]

There are glues intended for polycarbonate. They're mostly solvent, and dissolve the plastic at the joint to make the bond. I'm pretty sure they don't dissolve glass -- darn near nothing attacks glass.

[Kent Adams]

Take one out and look at the edge ... AFAIK tempered glass is green on the edge.

Unfortunately, that's not possible unless I want to destroy the stile and rails.

[Ole Anderson]

Scratch test with a steel point in a corner of the pane?

[Jamie Buxton]

Scratch test with a steel point in a corner of the pane?

Trying to scratch tempered glass is not a great approach. Tempered glass is strong because the surfaces are in high tension. If the surface gets a stress riser -- aka scratch -- the panel is likely to collapse into a pile of chiclets.

[Peter Quinn]

They are almost definitely using glass. Poly carbonate turns an off color after long exposure to UV, sort of clouds and yellows, not a good feature in a door. I'd be pretty surprised if masonite were using anything but glass in a door.

[Justin Ludwig]

Throw a rock at it. If it shatters into a thousand little pieces then it's temper glass. Buy new glass.

[Jason Beam]

Unfortunately, that's not possible unless I want to destroy the stile and rails.

So you have no way to replace one if it breaks?

[Gary Muto]

I had a door like that many (~20) years ago. It was single pane tempered glass. I think by law it has to be tempered but I'm not sure if the glass is that far from the floor. Anyway the glas can be replaced. You remove the 1/4 round trim on the in-side to replace the glass. The outside trim around the window (what's it called?) is part of the respective rails and stiles.

[John Aperahama]

Replacing said glass would probably cost more than the door.

[Lee Schierer]

If you tap on tempered glass with a ring or other metal object you will get a click. Do the same on polycarbonate and you will get more of a clunk.