replacing short windows - Contractor Talk - Professional Construction and Remodeling Forum

Home Serve · 12-12-2008, 08:06 PM

How do you guys do replacement windows for windows under 24" tall? We did some today that are 21"x63". We usually cut all the way back to the jamb all the way around and then trim inside and wrap outside. This still leaves too much wood/vinyl surrounding the window in my opinion (from outside you have the brickmold, vinyl frame, vinyl sash). That is a lot of bulk on a small window. I've played with the idea of removing the original window jamb altogether to increase the height of the replacement window in order for it to look better. Can't quite picture the entire process to make it efficient. Seems like quite a bit of additional labor.
Ideas?
Thanks,
Dave C

dougchips · 12-12-2008, 08:26 PM

Home Serve, small windows are hard because the frame size is the frame size and the trim size is the trim size, in most cases you will see very little glass compared to the frame. I think my smallest is 11x16 and the window looks silly but since it's a basement window surrounded by stone I could not offer a larger opening.

A W Smith · 12-13-2008, 12:31 AM

sounds like a slider. if the frame for a replacement is overpowering the opening consider a sash kit from Marvin or similar

Tru_Blue · 12-17-2008, 01:32 PM

There's several options:

1. I prefer full tear-out replacements for short windows. This method will give you the most visible glass height and less bulk. Measure the window from the inside of the home between the jamb or casing, as if you were measuring for blinds to fit between the jambs. Add 3/4" to all four sides to get the frame size that is to be ordered. Example: if the rough opening of a window (stud-to-stud) was 24 x 24, the frame would be around 23-1/2 x 23-1/2, the sash opening (inside of jamb to inside of jamb) would be around 22 x 20-1/2 (the height gets shorter because of the pitch of the sill). Add 3/4" to all four sides and you would order a "new construction" frame size of 23-1/2 x 22. If it's a clad wood window you're ordering, from the inside it will look like the same size as the previous window, and if one has existing blinds between the jambs they would still fit the same way. If it's a vinyl new construction window you're ordering, you'll need to add jamb extensions to the interior with approx. the same result.

2. Put a replacement unit between the existing jambs. Using the same example: if the rough opening of a window (stud-to-stud) was 24 x 24, the existing frame would be around 23-1/2 x 23-1/2, the sash opening would be around 22 x 20-1/2 (the height gets shorter because of the pitch of the sill). The retrofit/replacement unit would be ordered to fit that sash opening, with the replacement unit size being approx 21-3/4 x 20 (give or take 1/4"). Since you would now have a replacement frame in the original frame, there will be noticeably less glass than the other method.

3. Replace the sash only. Order a new wood or clad wood sash (presumably double or triple glazed with Low E glass). Reuse the same frame, wrap exterior if needed. This method allows for the most visible glass area.

tomstruble · 12-20-2008, 12:15 PM

i like to rip the entire old unit out also and some window manufactures insulated extension jambs and snap on exterior trim that is not too expensive

A W Smith · 12-20-2008, 12:51 PM

Quote:

Originally Posted by Tru_Blue

There's several options:

1. I prefer full tear-out replacements for short windows. This method will give you the most visible glass height and less bulk. Measure the window from the inside of the home between the jamb or casing, as if you were measuring for blinds to fit between the jambs. Add 3/4" to all four sides to get the frame size that is to be ordered. Example: if the rough opening of a window (stud-to-stud) was 24 x 24, the frame would be around 23-1/2 x 23-1/2, the sash opening (inside of jamb to inside of jamb) would be around 22 x 20-1/2 (the height gets shorter because of the pitch of the sill). Add 3/4" to all four sides and you would order a "new construction" frame size of 23-1/2 x 22. If it's a clad wood window you're ordering, from the inside it will look like the same size as the previous window, and if one has existing blinds between the jambs they would still fit the same way. If it's a vinyl new construction window you're ordering, you'll need to add jamb extensions to the interior with approx. the same result.

2. Put a replacement unit between the existing jambs. Using the same example: if the rough opening of a window (stud-to-stud) was 24 x 24, the existing frame would be around 23-1/2 x 23-1/2, the sash opening would be around 22 x 20-1/2 (the height gets shorter because of the pitch of the sill). The retrofit/replacement unit would be ordered to fit that sash opening, with the replacement unit size being approx 21-3/4 x 20 (give or take 1/4"). Since you would now have a replacement frame in the original frame, there will be noticeably less glass than the other method.

3. Replace the sash only. Order a new wood or clad wood sash (presumably double or triple glazed with Low E glass). Reuse the same frame, wrap exterior if needed. This method allows for the most visible glass area.

1) unless its an aluminum window. which many old slider are, Then you have to tear the entire window out. I like to measure rock to rock width and add 3/4 assuming 3/8 rocked jambs, same as height because a 3/4 wood sill gives me another 3/8 leeway to allow for sill slope, I give my manufacturer the opening size and they "hold back' from that 1/4 on the width and 1/2 on the height.

2) replacements in existing frames I measure sash opening from jamb to jamb and head to sill against window stool. (the smaller dimension of the sill slope), I round off to whole numbers and my manufacturer holds back from that. IE a bathroom window of 2/0 3/4 becomes 1/11,3/4 - 3/3,1/2