Looking for a set of channel balances

Question

We need to replace a set of channel balances in a single-hung vinyl window. The existing balances are not broken. However, another contractor replaced the existing glass with laminated safety glass. The sash now weighs too much for the factory springs, and won't stay up.

The sash now weighs 30 pounds. I have attached photos of the existing balances. The metal track on these is 20-5/8" long, 9/16" wide, and 9/16" deep.

Please help! This issue is holding up a real estate deal, so we need to get some functional springs as quickly as possible.

- Mike

Bob · Accepted Answer

Thanks for writing in, Mike. It makes sense these balances would be much too weak to work for a 30 lb window. For a sash with that exact weight, you'd need balances with a stamp of 20-9 instead, which will carry 28 through 31 lbs. Note that this information is based on 2 balances per sash. Balances are designed assuming friction in the jamb weather-strip will carry a portion of the weight, so suggested sash weights are approximate.

In any event, we can proffer the right balances for you; just keep in mind they'll have to be custom made due to their unique length and configuration. I am sending you an email with a custom link to order (2) of these balances. Let me know if you need a different amount or have any other questions. Many thanks.