Are window mounting straps necessary at bottom?
AdamPNW
| Posted in General Questions on
Hi all,
I’m installing European style flangeless windows (in the middle of the wall) and my plan is to prep the RO with a beveled sill (only the portion under the window) and back dam. But it seems like the back dam will be in the way of the mounting straps at the bottom.
I could install the back dam after the window, on top of the straps, but it seems like detailing this to be air/water tight would be problematic.
Can I just eliminate the straps at the bottom?
I’d appreciate any ideas, I think I’m missing something more obvious. Thanks!
Adam
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Replies
Adam,
Leaving aside any issues around the manufacturer's installation instructions...
What are you suggesting as an alternative to stabilize the window at the sill? The back-dam will stop any movement inwards, but you need something beyond relying on the inherent strength of the window extrusion to stop any movement to the exterior. Solve that and practically you can eliminate the straps.
The last time this came up the OP suggested attaching L brackets to the rough-sill, and screwing them into the window frame.
Right ok. Agreed. Thanks!
Unless the window is directly against the backdam (as a mechanical stop), what's the problem with putting a bent jog in the straps?
Yes I may be able to do that, but it’s tight. If the spacers keep the window above the back dam, I could keep them straight (see drawing), but that’s also a narrow margin. Perhaps the back dam only needs to be 1/4” proud of the bevel.