Aluminum storm window repair redux and sources

[TimR]

I finally got around to pulling out a cracked aluminum storm window for repair.

There's nobody in my area who will touch these so I'm doing it myself, and the last one was nearly impossible. The aluminum pieces are staked together with dents and not easily removable, getting the acrylic piece in was very difficult, etc.

But to my surprise this window is a friction fit. There is a thin rubber gasket on the glass, and the four aluminum channels are separate and just press on. I have a couple more of this style on basement windows that are missing the storm, and worth the effort to build, and one more with a crack.

Can you recommend sources for aluminum channel in this size? I assume I buy big pieces and cut to size. Also the local supply of acrylic is limited in thickness and I would probably order the right ones. I'm thinking one of you has probably done a few of these home builds.

Or is this a dumb idea?

[hubops]

I'm finding it difficult to imagine the aluminum frames being only a friction fit - but maybe I'm reading you wrong <?>

... are the " dents " actually a spot-weld ? Also - are these aluminum storms installed on aluminum windows or over old wooden windows ? Photos would be nice.

My first home - owned early 80's ; built late 50's - had aluminum windows - the window replacement was to be my first big upgrade. In winter, the inside of the windows wouldn't just sweat - the aluminum would have frost/ice build up .. on very cold days the glass would frost-up also .. The vinyl or vinyl-clad windows in my subsequent homes were much better. John T.

[TimR]

These particular windows are basement windows with aluminum frames and I think some steel mountings. The conduction through the metal has to be several orders of magnitude greater than that through the glass/plastic. I don't think there's any way to make them energy efficient but I would like to reduce infiltration. Also with a plastic storm in place, the damage from maybe a lawnmower or leafblower thrown stone is minimized. I had one window break from an impact that pushed the screen against it some years back, we never figured out what did it. It may have been a deer eating the bushes and stumbling a bit.

But yes, these windows are a friction fit assembly. There is a U-shaped rubber gasket (now hardened into brittledom) that slips over the glass. Four pieces of aluminum channel with 45 mitered corners slide onto the gasket, and the assembly is quite solid. There is no corner piece on these to slide up and down the casing frame, they are just a close fit side to side, and enough slop on top to be able to push one up to clear the bottom trough for removal.

The dents on the other style are not a spot weld. They are either a dimple or a couple of straight lines pounded in. The corners are held together with L-shaped plastic pieces which break when you disassemble.

The glass I've removed is 0.101 inches on my calipers. I may dig out the micrometer and double check. The local box stores sell acrylic in .080 and .12, I see I can order in .093 which is probably close enough. But there may be a much better source of plastic replacements.

[TimR]

Update: I finished repairing the window. One big box store carried .093 but wouldn't cut it, the other would cut it but only had .080 and .125 thickness. So I bought the .093 and scored and cut it myself, had to clean it up with a sander after because it's hard to snap it cleanly.

However the window didn't fit back in right away because the four aluminum channel pieces warp from the force of taking it apart. You can't hammer them flat because they spring back. So it was an iterative process of eyeballing the curve, bending by hand, trying the piece, getting one side to fit and now the other doesn't, etc. Took a while but in the end the window is back in the frame. I'm rethinking whether it's worth the effort to build any from scratch.