| Hi Milemarker, this is not my field, but I have used tempered glass and I don't think it is the same as heat treated. If I remember correctly, the tempered is the stuff that breaks into a million pieces so it won't pose a safety hazzard. But the temps of a fireplace, I'm guessing, not.
But those prices, I would think you could but a whole insert stove for that. Let's hope someone posts with some real numbers.
Good luck
Bud |