Reinforcement for Large
Copper Foil Project.
by Sue Callahan
(New Bern, NC)
I am constructing a large window (not to be exposed to the elements) that is 39" X 60", in copper foil. I would normally use lead came for a project like this and reinforce with rebar. However, my customer wanted copper foil. I am trying to decide how to reinforce. I always frame in zinc came for strength and I am using 1/2" H channel zinc for this window. When using restrip, how much is enough? I can not find guidelines for how much to use. Do you think restip would be enough strength for a project of this size? I can use rebar, which I am much more confident about (it has stood the test of time in many historical windows) except that the design does not lend itself well to the straight horizontal lines of rebar. I have sent for a book on reinforcement guidelines from SGAA but it has not arrived yet and may not answer my question about restrip. Please help if you can, Thanks,
Visions In GlassAnswer
That's one big window to be foiling. I'd be leading it too! A lot faster and easier, in my opinion.
Reinforcement is necessary on larger windows. As a rule of thumb, a window more than three square feet should be reinforced.
Use restrip every 1 to 1 1/2 feet on a panel as large as yours. I'd run it in both directions, (side to side as well as up and down) and make sure you use it on any hinge joints as well. Run the restrip from edge to edge in both directions.
Restrip is extremely strong. New data is showing that it is as strong as rebar. Of course, rebar has been around a long time, and restrip is new in comparison, so time will tell. I'm sure we won't be around for the final analysis!
I'm trying to picture the panel in relation to one I built for our game room. It is 5 1/2 feet long, and 1 1/2 feet high. It is foiled, reinforced with restrip and has a zinc frame. It has been in place for 5 years, near a door that opens and closes frequently. It is not exposed to the elements, it's between the game room and a hallway. It has no bows, cracks, nothing at all to indicate that it should have had more reinforcement.
With the restrip and the zinc frame, you shouldn't have to worry about the panel flexing. It should be as solid as a rock. However, you be the final judge. Since I can't see the panel, I can only give you advise on what you have told me.
I hope this information will help you make your reinforcement decision,