measuring windows

Old 12-31-03, 01:19 PM
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Cool measuring windows

I need to replace my old double hung windows. I want to replace them with vinyl tilt windows, cause I am tired of climbing a ladder to clean them! Do I measure from the rough opening or what? Also, the sills and outside trim is rotted--do the new ones come with these? I am saving the stained inside trim to reuse; nothing wrong with that! Someone told me the sills rotted because we have masonite siding???? Anyone heard of such a thing? Any help is greatly appreciated!! Thanks a bunch! kay
Old 12-31-03, 04:26 PM
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Measure the opening that you will be leaving. Subtract 1/4" from the width and 1/8" from the height. THAT is the size you need to order. MAKE SURE that your supplier knows that you are ordering the exact size you want -- otherwise they will reduce the measurements, and you have gaps to fill!!

Wood dbl hungs can be installed by removing just the sash and leaving the existing frame in place. Replacing the sills isn't that difficult, and replacing the outside trim is even easier. No, your new windows won't come with the exterior trim attached. You'll want to order them "block frame" -- no exterior trim and no nail fin. But you will probably need the sill trim piece for each one. Your sills are sloped -- about 7 degrees. The new window will sit in the opening with the inside edge supported by the sill -- you need the trim piece to support the outside edge. If you have access to a brake, you could make your own trim pieces, but I wouldn't rent a brake just for that.

The rot occured due to water damage and probably a lack of maintenance. It happens regardless of the kind of siding that you have. My house had masonite siding for the 1st 40 years of its life -- before the vinyl went on -- and I had no rot.
Old 12-31-03, 04:53 PM
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Here's my canned "how to"......

and I would rent a brake to do the outside trim work.


How To Measure for Replacement Windows
Wood Double Hung Version

Wood double hung windows are what vinyl replacement windows were “really” designed to replace, though they definitely can and are used in other situations.
The thickness of a replacement window frame is 3 ¼”, which is the combined thickness of 2 standard wood sashes. The replacement window goes in the space where the old wood sashes slide up and down.

In windows that date from the late 50’s forward, wood window makers used fairly standard sizes and construction methods. Standard sizes start around 18”, then go to 20”, then 24”, 28”, 32”,36”, 40” and occasionally you see a 44 or 48” on WIDTHS.
The sashes will generally slide up and down in an aluminum or plastic track.

Heights usually run 38”, 54”, 62”, 72”.

For example: a wood window called a 2/0 x 3/2 is a 24” wide by 38” tall window.
IMPORTANT: Window sizes are always given width first, height second. Don’t get that mixed up !

When you measure the width, you would get REAL close to 24” when you measure inside the area where the sash slides up and down. The height will measure about 37 ¾”or so, measured from the top of inside sash track to the TOP of the sloped part of the sill where the sash makes contact when it is lowered.

So for that window, I would order a replacement 23 ¾” wide and 37 ½” tall.
I order my windows “EXACT SIZE”…..if you don’t tell them that, they will automatically cut your measurements ¾” or more……..on the assumption it’s easier to fill in than tear out, I guess…..If you do what I tell you, there is just enough gap to slide the unit in and leave a caulk joint…..otherwise, you have some serious insulation stuffing to do, plus more trim problems later. GET EXACT SIZE.

On older double hungs, like the type that have rope pulleys and sash weights back in the wall, you measure the same way, but the sizes will vary quite a bit more…..there were far less standard……they sometimes vary ½” or more even between window to window that appear the same size.
Old 01-01-04, 09:46 PM
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Thank you, Andy & Lefty, for your advice & help. I really appreciate it! kay

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