Lrg Window – Replacing Sin. Pane w/Insul

Hello all,
I just purchased a new old home (1954) — the living room has a very large window bay, approximately 12’wide x 9’tall with hoppers at the bottom and fixed panes at top – the fixed panes are approx. 24w” x 7’h and they are single pane windows. These windows face north, and I live in the northeast, so needless to say it is pretty damn cold in that room. I’m strapped for cash as most new home owners are, and I know it would be a fortune to fully replace the window bay — so I would love to just replace the panes with insulated glass panels.
The inside frame of the window is fairly deep – 3.5″ and the pane is held in place by basically a piece of standard base molding. I was thinking I could carefully pull that out and rip it to accomodate the larger thickness of the insulated glass panel.
Does anyone out there have experience with this and have some recommendations/advice on pitfalls etc… I guess my biggest concern is removing the large old piece of glass without killing myself. I’m also concerned that the new heavier double pane will affect the window frame and cause issues opening the hoppers below.
Anyway – hopefully someone has some experiences to share.
Thanks
Sean
Replies
Major weight difference with insulated lites. You presume it won't fall off the house... Or by "bay" do you not mean extruding?
Good luck.
PAHS Designer/Builder- Bury it!
For deep framed windows I've made new frames that fit inside the existing frames. Strips of adhesive foam sealed the edges and a single layer of heat shrink plastic for the 'glass'. They worked very well. Removable if not in winter.
I'm now experimenting with a layer of plastic on each side of the frame, for more insulation. Should be significantly better for almost no extra cost.
For a more permanent set-up, you could make the new frames to fit insulated glass units you could special order. Caulk the edges, paint, and I'd think they'd be barely noticeable.