multi-pane glass door

hi all, I'm trying to get the correct thickness of glass for my control room /tracking room doors, but nobody carries the door with that thickness in my area, and special order doors were quoted at 450$ ( NO GLASS!). I'm looking to see if it's ok to put several layers of glass together to create the desired thickness, as opposed to using one thick pane of glass. just to be clear, the glass panes are sandwhiched back to back like layered drywall. for example: 1/8" + 1/4" = 3/8" this thickness is one of the two doors I need, the other is 1/4 + 1/4 = 1/2) will this cause rattle or chatter problems? will this be a multi leaf issue and break the MAM law? heres a link to my build diary to see what the context is. http://www.johnlsayers.com/phpBB2/viewt ... highlight= Thanks for your help. kevin PS - Rod, great book!

If there is the slightest air gap between panes in a single "leaf", it will cause a loss of isolation - the narrower the gap, the higher frequency this "short circuit" will be. IF you try to get two panes tight up against each other, I'd be absolutely amazed if they didn't rattle. I went looking for DIY laminating material a while back, and came up empty - I still think there should be a double-stick tape available somewhere that's available in wide width rolls, that would stay clear and be usable for this (but I've not found it) - if this were available, and if you were careful enough, you'd basically be making your own "safety glass" of sorts - Can't tell from the skp, are you wanting two separate doors one in each frame? IF so, then only ONE pane of glass per door, and as thick as possible. Maybe buy a standard french exterior door, and have a glazier replace the insulated (these days) pane with safety glass? (Some french doors have a single glass with fake "dividers" to make it look like individual panes, that's the type I mean) Isn't gonna be cheap no matter what you do, wish I had more to offer on this... Steve

steve, yes, there will be a door on each framed wall (between tracking room and control room). there will be one additional door in the tracking room (in the curved wall section) that leads to the unfinished 1/2 of the basement (which will be a single solid core door , if there is still too much bleed through to the upstairs from that side, then I can always frame in an additional door, in either case, I'm not concerned as much with that side of the room). i thought of your suggestion of using a standard door and replacing the glass, and that might be the way to go. buy a standard french door and take it to the glass company and have them replace the glass with a single thicker sheet. cost wise, it's still cheaper than having custom doors made by about half. rough cost breakdown french door $250 glass 12sqft 1/2" = $200 labor $100 two other considerations that may negate the correct door glass: the window glass is 1/4" laminate and I've been leery on the flanking through the hvac duct that penetrates both rooms above the wall in the ceiling, the ceiling will be dbl 5/8th, and I will wrap the duct in insulation, so I think this just might be one of the situations where "it's the best I can do for now". let me know if you have any other comments or ?? thanks for your input, kevin

IF that HVAC duct actually ENTERS both rooms, and doesn't have at least two 90 degree bends between entry points AND duct liner inside the duct, it WILL cause undue flanking. IF it's just passing OVER the rooms, then an extra layer or two of gyp board (if your framing can take it) would help flanking quite a bit... Steve

hey steve, sorry for the delay. as for the ducts. Only the supply will actually 'enter' both sides of the wall, however, the supply in the tracking room is taken off of the main trunk (the metal duct shown) and then feed through several feet of flex duct, it does a 90 more/less, (see of my photos for what I mean) and let me know what you think. As to address the flanking, I'm planning on double drywalling the ceiling (below the duct) and wrapping the duct in insulation. kevin.

I'm not trying to beat a dead horse, but I'm still looking for a solution to the dual doors in the double wall. I was offered exterior full lite (full glass) doors that have acoustic isolation glazing (the guy at the store told me they are identical to the gas filled thermal insulated panes, except without the argon gas, IE, a vacuum). Would this glass vacuum sandwhich act as one layer, or would I still end up with a 4leaf system w/ two of these doors? Does anyone know (or guese) at the amount of isolation difference between two doors with the thermal dbl glaze (results in a 4leaf system)vs replacing the thermal glazing w/ 1/2" glass? I guese my options at this point are: purchase 2 interior doors (and seals) and only have an 1/8th glass in each door for a 2 leaf system (prob not a good idea), or purchase 2 exterior doors and just live with the four leaf system. or if the isolation is really bad, replace the thermal glazing myself w/ solid glass. I'll post some more pix this week from progress, i still need to order a snake of some form to link the rooms, thanks for the help kevin kevin