measuring for replacement windows

Old 07-08-03, 09:20 PM
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measuring for replacement windows

I just purchased an older home that needs some replacement windows and some new windows because the frames are rotten. Can someone take the guessing game out of measuring for the replacement windows. They don't seem to be difficult to install.
Old 07-09-03, 03:00 AM
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When you say the frames are rotten, does that mean you plan to pull the WHOLE old window out and use a COMPLETE new window ?

Vinyl replacements are designed to remove the sashes and leave the old frame in place.

Which way you're going will depend on the measuring advice.

Also, approximate age of the existing windows and exterior siding or masonary finish will help in an answer.
Old 07-09-03, 04:24 AM
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I'm actuially replacing both types. I need to know how to measure for replacement windows. I am reframing the other ones and know how to do those. The existing outside is allum siding over wood. The origional windows are on the house from 1958. sills look ok.

Thank you for the quick response
Old 07-09-03, 08:20 AM
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Posts: n/a that I know what you's my "clip and paste" doc for measuring for typical replacement vinyl windows.

Want the C&P "how to install" too ?

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 07-09-03, 08:23 AM
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Ah, heck...I got Word open anyway, I'll just CandP it....

How to install replacement vinyl windows
If you have standard double hung wood windows

First, I’m assuming you have read my “how to measure “ and have your windows ready to go in.

1. Remove the storm windows. The wood strip or ledge they were screwed to is the “storm stop”. Usually a strip of wood about ½ x ½” that extends back under the exterior moulding. In addition to giving a place to mount a storm window, it also serves as the stop for the outer most sash, the upper one.

2. You can either remove the storm stop with a wood chisel and take the sashes out to the outside…..which I do IF the inside is painted up and I don’t want to disturb it…..or you can remove the inside stop ( the one that holds the lower sash in place as it slides up and down). Don’t take off the top outside stop. Not necessary. If the inside stop is stained and will come off easy, go that route. Do take off the top inside stop…..necessary…but save them for reinstall.

3. If you have fairly “modern” windows with the aluminum tracks, just raise both sashes to the top, slip a bar or hammer claw in behind the track and fold it inward…..usually couple staples holding it, then grab both sashes together and jerk in the direction you took the stop out. The whole mess will come right out in your hands, be ready. People put deadbolts on their doors and 4 little staples hold the windows in…..ahahahahahahahaha

4. If you have the older rope and pulley type window, after taking one of the stops out, cut the sash cords on the first sash( boom/boom…those were the counterweights falling back in their cavity) and take out the sash. Then take out “parting stop”…..a 3/4x1/2” strip set in a dado ( groove) in the side jamb. Probably painted all to whizzz, but pry with a small chisel or screwdriver and it will pop out. Then you can cut the cords to the other sash and take it out.

5. On both, there is a parting stop at the top of the window…remove it too or the new window won’t go in place.

6. There is a type of wood double hung I call “pop and go” windows. They used a spring loaded aluminum strip on one side to put pressure against the sash as the method to hold it in place. All you do to get those out is grab the sash, jerk toward the spring loaded side ( usually the left side from inside looking out) and the sashes will come right out. Then take the aluminum tracks out ( screws set in pockets). The pocket on the spring side is deep… need to measure this type window slightly more in width. Usually a 28” wide window I make 28 ¼” so it will set in that pocket a little better….and you still have to stuff some insulation there.

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7. Now set your new window in the frame. Put it tight against either the inside or outside stop, whichever you didn’t take off. Level, make sure the new window is square, then use the four screws that came with it to install. If your windows are tall, I run another screw in the side jamb ABOVE the travel point of the sash shoe on the inside track to hold the jamb securely where you want it. Don’t bother using the jamb adjusters that come with them, most are junk.

8. Run bead around the outside on sides and top. Stuff some fiberglass insulation under the bottom where the new window is flat and the wood sill slopes away. Then you can slip the sill extension piece ( that flat pc with a little lip that came with the window) onto the bottom of the window to fill that gap, and install a couple of wood strips to replace the stop you cut off. Caulk and paint as needed….OR

9. I make aluminum trim to cover all the outside wood. If you can rent a sheet metal brake, buy some aluminum trim coil and do the same. This is a deal where pictures would be worth a zillion words…..maybe I’ll set up a website one day to show you how. This finish work is what separates the amateur work from the pro work.

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