View Full Version : Calcutlating the weight of glass

10-01-2003, 08:53 PM
Is there a formula for calculating the weight of glass. I am using a .5" thick piece of tempered plate glass that is 8 feet by 8 feet. I know a cubic foot of glass is 161 pounds, but I am not sure waht kind of glass that would be.



10-01-2003, 09:05 PM
Depends on how close you want to be with the weight. My tables give 2500kg per cubic meter which is about 156 lbs per cubic foot. This is for typical float glass, so I guess somewhere between your figure of 161 and mine of 156 would be on the money. 415 lbs against 429 lbs.


10-01-2003, 09:40 PM
If you want to be sure what your particular type of glass wieghs,use the specific gravity test http://bbs.homeshopmachinist.net//biggrin.gif

10-01-2003, 11:41 PM
I have a simple test for weight, call the vendor.

Thanks for the help.


10-02-2003, 02:52 AM
Plate glass has a density of 2.4 grams per CC. Pure silica glass is 2.203 g per CC. Borosilicate glass is 2.44. Lead crystal is around 2.8 depending on lead oxide content.

10-02-2003, 05:27 AM
If you can heft the panel, put it on your bathroom scale, or maybe two of them. divide the weight you get by 2-2/3 (2.66667), and that'll be the weight per cubic foot, since your 8'x8'x0.5" comprises that many cubic feet. If you can't heft it, get somebody to help you. If you need to use two scales, add the two weights you get to bet the total weight.

10-02-2003, 01:39 PM

[This message has been edited by pgmrdan (edited 03-08-2004).]

10-02-2003, 01:54 PM

Mind if I ask what you are doing with a piece of glass like that?

10-02-2003, 04:56 PM
I'd also like to know the use of the glass, and the need to know the weight that precisely. Or would you have to kill the lot of us if you told us?

Paul Alciatore
10-03-2003, 02:52 AM
Bathroom scales are not that accurate: +/- 5 pounds or so. Also, the calculations from it's density could be off if the thickness varies from the nominal. I'm not too sure I would trust a density figure from the supplier either.

If you need an accurate figure I would suggest weighing it with a certified scale or carefully weighing a 12" x 12" sample on such a scale and multiplying up to your size.

10-03-2003, 03:18 AM
My digital bathroom scale is accurate to +- 250 grams. It is made with plate glass and load cells.