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Community and Q&A

I want to place insulated glass units in a frame wall.

Redstone Group LLC | Posted in GBA Pro Help on

I want to place insulated glass units in a frame wall. At this point, the wall is studs with plywood sheathing. What is the best way to frame, secure and trim these IG units?

The middle window is 6′ by 6′. Flanking units are smaller. Windows face south. The windows are fixed, glass only, no nailing fins. Exterior trim will likely be rough sawn walnut because it holds up to moisture. Located in SE Iowa

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  1. GBA Editor
    Martin Holladay | | #1

    Fixed windows require several elements in addition to the IGU (the glazing). You need a sill, jambs, and a head. The sill needs to project beyond the jambs and be wide enough to drip moisture beyond your siding. The sill needs to have ears that are wider than the exterior casing. You need glazing stops, setting blocks, and butyl glazing tape to seal the IGU to the window frame. And you need a rough opening to put your window in.

    If you know all that, great. If you don't have your window frame yet (your sill, jambs, and head), you'll need to build it. Or if you prefer, you can always buy a fixed window from a window manufacturer.

  2. Expert Member
    Malcolm Taylor | | #2

    As Martin said, it's best to build a frame - that is to make a window. Placing glazing in framing with just stops is asking for trouble.

  3. Redstone Group LLC | | #3

    Thanks Martin and Malcolm.

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