Window measurement

Old 04-27-11, 05:08 PM
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Join Date: Jun 2009
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Window measurement

Hi folks,

I wanted some tips regarding measuring for a replacement window.

I have the following window. Well, there's 2 of them, but this is a representative of both:

When I measured, I followed the instructions and took 3 measurements for the width and 3 measurements for the height. For the width, I just measured from wall to wall. But for the height, I measured from wall to the top of the ceramic sill.

For the 1st window, I got the following (in inches):

1st measurement (top) - 51 3/4 "
2nd measurement (middle) - 51 3/4"
3rd measurement (bottom) - 51 3/4"

1st measurement (side) - 49 1/4"
2nd measurement (middle) - 49 1/4"
3rd measurement (side) - 49 1/2"

For the 2nd window, I got the following (in inches):

1st measurement (top) - 51 3/4"
2nd measurement (middle) - 51 7/8"
3rd measurement (bottom) - 51 7/8"

1st measurement (side) - 49 1/4"
2nd measurement (middle) - 49 1/4"
3rd measurement (side) - 49 1/4"

For both windows the depth measurement was 4 1/4".

Here is a depiction of the measurements:

For the sill, I measured 3/4" from the top to bottom as seen here:

From various articles, it states that I have to pick the smallest dimension. For the width, I'm straightforward. But for the height I'm assuming that I also have to add the sill measurement, right?

Also, do I need to add a correction factor to the measurements? And when I order replacement windows are these specified as exact measurements or rough opening?

Thank you!
Old 04-27-11, 07:37 PM
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Join Date: Mar 2004
Location: Vancouver, BC
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I'll chime in here for some feedback, and hopefully some help.
I would try to stick to rough opening measurements. Not sure if you're planning on changing out those jalousie windows for something else.. or the same.
I would not include the sill in the height measurement. The sill will probably have to be removed and/or changed out for something else (finished trim or a new sill...).
The existing jalousies are most likely attached to the framework from outside .. and covered in your siding or the that, too is a concern. With windows, there is work to be done on both sides of the installation...
Try to determine your actual R/O (rough opening) to get to the measurements needed, for what you want to replace that 'space' with..! (window wise...).!
Trim work/moldings will cover any gaps that will arrise with the new install, along with some insulation around the frame/RO....
It's all do-able...
Perhaps some others may chime in as well....
Let us know how it goes...
Old 05-01-11, 05:31 PM
Join Date: Jan 2011
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What's on the outside walls of this home? If it's just vinyl siding I'd go with new constrution windows not replacement one's on this one. The main reason is those windows need to come completly out and to do that your going to have to remove the whole window frame and all. On the outside there's a flange with screws in it holding in that window. A new constrution window will also have a nailing fin so no air or water can leak in.

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