Window jamb extensions

mike13June 14, 2006

I'm in the process of finishing off an attic space. The gable walls are 3.5" thick (2X4 construction). To increase the insulation R-value I'm making a double wall which will result in a 7" wall thickness. There is an existing single double-hung window which I need to extend the jambs on.

Anyone with recommendations on the best way to accomplish this?

Thanks,

Mike

Thank you for reporting this comment. Undo
early1

I'm not going to claim to be an expert, but I think all you need to do is to rip some 3/4 stock to the required width. You might try attaching to the existing jambs with finishing screws rather than with nails. Predilling for the screws will avoid splits. You don't need many screws because the casings will also hold the extension jambs in place. If you are using stool stock at the bottom you can do something similar. Shims may be helpful underneath. Worst case scenario is to shim and nail the extensions to the framing, but it's nice to avoid this. Another alternative is to drywall right to the existing jamb and corner-bead the corner (trimless look).

    Bookmark   June 14, 2006 at 12:31PM
Thank you for reporting this comment. Undo
wbralick

I had to do this in my basement and it was fairly easy. I just bought some clear pine and ripped it to the correct width and then cut some some slots on the vertical pieces for the horizontals to fit into.

Because my pieces were about 2" wide I chose to shim between the framing and the extensions so that they would be rigid. Then I used a 2" brad nailer to attach them.

Bill

    Bookmark   June 14, 2006 at 6:09PM
Thank you for reporting this comment. Undo
PRO
Brushworks Spectacular Finishes

or you can visit a lumber yard and buy jamb extensions from 1/4" to 2 1/2"

Michael

    Bookmark   June 16, 2006 at 12:06PM
Thank you for reporting this comment. Undo
taw9370

We have existing anderson casement windows for 2x4 wall, we are going to a 2x6 wall, our local lumber yard ordered us extension jambs for 2x6 wall from Andersen, we just took out the existing 2x4 jambs, and added the 2x6 jambs.

    Bookmark   June 16, 2006 at 1:38PM
Thank you for reporting this comment. Undo
mag77

You'd be better off replacing the old window than doubling the wall thickness.

    Bookmark   June 16, 2006 at 10:50PM
Sign Up to comment
More Discussions
Kitchen cabinet rankings- middle of the line
We are redoing my kitchen. It is 11x13. I saw a ranking...
Jessica Galvin
Small bath remodel - problem tub size
I could use some advice. We decided it is high time...
thomis
Structural Engineer - What do I need to Know?
I'm planning a kitchen gut/remodel in my three-story,...
Carrie B
Moving window vertically
Hello - we are purchasing a house and trying to think...
bethanympuku
question about getting a bid from contractors
We're getting ready to put an addition on our house...
sparkleblue75
Sponsored Products
Each 108"L Zenith Curtain
$69.90 | Horchow
PetSafe Screen Storm Door Pet Door - P1-ZB-11
$25.99 | Hayneedle
Pearl Textured Dupioni Silk Single Panel Curtain, 50 X 84
$158.95 | Bellacor
Capri Denim 84-inch Grommet Panel Pair
Overstock.com
Waverly Eastern Myth Radish Panel Pair - 12731100X084RED
$84.98 | Hayneedle
Serena & Lily Half Moon Window Panel
Serena & Lily
Jaipur Batik Rod Pocket 108-inch Curtain Panel
Overstock.com
Wild Horses Antique White 68-Inch Steel Frame Curtain Rod Valance
$168.95 | Bellacor
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™