To double glaze or not to double glaze..That is the question

Hello fellow sound geeks. Let's play a game called - Help me make decision! I have built some killer doors for my new studio and am now about to set some glass in place. I have two options; 1 - The tried and true, double glaze system. One pane of 15mm and another 18mm (both angled) with an 60mm air cavity in between. 2 - I have a friend in the glass business who can get his hands on quality laminated 40mm glass left over from a previous job. Because of the thickness, I'd only be doing a single glaze, installed on a slight angle. Now, I'm pretty sure the double glaze way of doing things would most likley yield better results but I'm talking like a $600 saving if i go with the 40mm stuff. It's time to play dudes! What's the better way to go?

Okay, let's continue the game. What is the door made of? Andre

I'll play too! What's the wall(s) made of?

Sweet! Lets roll the dice The doors - Steel frames with 20mm of timber for the face, sides and back. inside the door there is a mix of lead impregnated vinyl, plasterboard and rock wool with and air gap in the very center. The cut out for the windows in the big doors are 750mm x 750mm. The smaller doors just have peep holes, 200 x 200. The walls are 338 mm thick. make upis as follows - 2 x 16mm plasterboard, 90mm stud with a butt load of insulation, 100mm air gap, 90mm stud w/ insulation, 2 x 16mm plasterboard. I'm thinking of maybe doing the 40mm glass for the 200 x 200mm "peep holes" in the smaller doors and doing the trusty double glaze system in the bigger doors. Damn! snake eyes! Your turn.

BRS wrote:

The doors - Steel frames with 20mm of timber for the face, sides and back. inside the door there is a mix of lead impregnated vinyl, plasterboard and rock wool with and air gap in the very center. Damn! snake eyes! Your turn.

So you door has no thickness. Correct? :D Seriously, the 40 mm glass single layer will be fine. Andre

Use it. A door don't need 2 panes. 1 door is 1 layer. you can't have two seperated layers making one door. Then you'll be talking 2 doors. And two doors needs 2 panes of glass, otherwise it makes no sense. So use that 4cm pane in you superdoor. If it save ye a bug, hurray. Hope the pane is the correct size, since cutting is not possible with laminated glass. BTW. Would you please stop crossposting.