Replacing Damaged Window Framing

Help Support House Repair Talk:

Rwh56

Member
Joined
Aug 23, 2011
Messages
20
Reaction score
2
I discovered carpenter ant damage to the framing underneath my double hung window. Ideally, I would like to replace the entire window sill plate and two of the supporting studs. How can I do this without removing the window, as the damaged studs and sill plate support the window? I could remove the window sashes and their counterweights to reduce the over all mass of the window. (Should have started on this during warmer weather.) Thanks in advance for any advice.

Rob H.

Window Studs and Window.JPG

Window Studs.JPG
 

tomtheelder2020

Well-Known Member
Joined
Mar 8, 2020
Messages
239
Reaction score
87
Location
95620
I am interested in what someone who knows what they are talking about says, but what I would do is: 1) attach sisters to everything using screws to anywhere that is solid; 2) apply wood hardener to old wood that is soft; 3) as much as possible, fill void space in original lumber with bondo or such; 3) screw sisters to filled areas.
 

Eddie_T

Well-Known Member
Joined
Feb 16, 2015
Messages
917
Reaction score
653
Maybe a board nailed to the full studs on each side with pieces of angle on each side to slip just inside those 2 shim blocks supporting the window. The all the bad wood could be taken out by cutting ,chiseling or whatever is necessary. Then rebuild and shim to support window.

Or do as Tom suggests and use a temporary cripple to support the sill plate while the worst cripple is removed/replaced.
 
Last edited:

bud16415

Fixer Upper
Staff member
Admin
Moderator
Joined
Feb 5, 2013
Messages
6,534
Reaction score
2,485
Location
Erie, PA
Looks like my house.



I would put a couple straps 1x4 or 2x4 across the full length studs both sides of the window frame one near top one near bottom and then drill and screw thru the straps and into the casing 4 places. That should hold the window in place.



Take out the blocks and start with cutting away the bad stuff. Keep in mind the sheathing is nailed to it from outside. Cutting it into chunks should let you pry it out and then snip off any nails coming thru. They are likely square nails or cut nails and are hard as a rock and might need cut with a 4” angle grinder then build back leaving the blocks out and going against the bottom of the window frame and sister in new studs to the good wood.

Are you pulling all the lath or doing drywall over it? If you add thickness to the wall you will need to extend the casings out a little so the window trims correctly. Down the road they sell replacement double hung windows that fit inside the old casements or just keep the old single thickness windows going another 100 years. That’s what I’m doing.
 

Rwh56

Member
Joined
Aug 23, 2011
Messages
20
Reaction score
2
I was thinking of putting block cleats inside the sash weight space, but it would be simpler to use Bud's idea of placing horizontal boards across the window case and adjacent studs and screws into the studs and window case. This solution is giving me encouragement to replace all three cripple studs and sill plate. Thanks! And yes, I will keep the double hung windows that look so much better than the new Andersen replacement windows, in my opinion. House dates from 1920.
 

Eddie_T

Well-Known Member
Joined
Feb 16, 2015
Messages
917
Reaction score
653
Remember that modern 2x4s are not a direct replacement for your studs.
 

bud16415

Fixer Upper
Staff member
Admin
Moderator
Joined
Feb 5, 2013
Messages
6,534
Reaction score
2,485
Location
Erie, PA
@Eddie_T brings up a good point. I sometimes have ripped 2x6 down to the size need when replacing the old real 2x4s. I also when ripping any of the old wood out that is good still hang on to it and place it back in because it is dimensionally correct when possible.

I see you have those new 1920 sash weighted windows. Mine are all the older 1870 models. :coffee:
 

BvilleBound

Active Member
Joined
Feb 24, 2021
Messages
27
Reaction score
20
Location
02571
Carpenter ants are attracted to moist wood. So I would also carefully examine the wood for evidence of rot and water leakage - common problems with window penetrations. If there is evidence of rot, the flashing around the window needs to be replaced, on the outside surface. Older homes are often 'wrapped' with tar paper which can become brittle with age, making this job more challenging. There are good resources available on the web describing how to flash a window properly, e.g. www.finehomebuilding.com/list/window-and-door-flashing-guide

If you need to replace the sill - perhaps due to rot on the outside - this also means that the flashing around the window will need to be replaced. Flashing is applied starting at the bottom, working upward.

Finally, you should air seal the framing and trim around the window after it is repaired. See: www.finehomebuilding.com/project-guides/insulation/air-seal-windows-and-doors

FineHomeBuilding.com is an excellent resource for high quality advice and instructions.
 
Top