weight of alcoa tilt window sash

Home Owner

Feb 21, 2015 4:59 pm

I notice that I have a choice of spiral balances depending on the weight of the sash. I have alcoa tilt-in windows, the one I am trying to replace the spirals for is 3'9" wide by 3' tall assuming the "sash" is the lower moveable part of the window. How do I go about estimating or finding out the appropriate weight range to use for this window? There is a etching mark on it that says ALCOA 1099, but am not clear whether this actually means anything in terms of identification. Would appreciate any suggestions.

4 Replies

Paul from SWISCO

Feb 24, 2015 11:54 am

Yes, you're correct: the sash is the part of the window that slides up and down and contains the glass. The best way to determine its weight is to simply remove it from the window and place it on a scale.

Home Owner

Feb 24, 2015 6:17 pm

Sash is 37.6 lbs the washer on the end looks to be black, the length is 35" and I swear the diameter is actually closer to 3/8 than 5/8, but it is difficult since it is plastic and in shreds. I notice that the only the spiral balances in that weight range and with a black washer are the 5/8 diameter ones. Again, these are ALCOA windows circa 1995 with a 1099 etch mark on them. Is there any way you know to confirm that the 5/8 diameter balances are the right choice? Also is it likely that I can use the old shoes rather than having to replace them? There are no channel cutouts and I am reluctant to use a spreader...

Paul from SWISCO

Feb 25, 2015 10:00 am

Well, in my experience Aloca uses our 5/8" balances very often. We also do not have an S900-35 balance that can support that kind of weight, so I think the 5/8" is more likely.

As for the shoes, as long as they aren't damaged I see no reason why you can't reuse them.