How do you get glass loose from a double pane window as in a peela window that slides across instead of up and down it appears to be held in place by some heavy duty putty that won't let go?

Answer 1

Pella uses butyl caulking so it will not harden, and so the glass can be replaced. If your window has a removable inner pane and a "stuck" outer pane, remove the inner pane and there is a removable wood stop that holds the outer pane in place. This wood stop is stuck very well with butyl caulking. Carefully pry out the stop, being patient and slowly giving the butyl time to give up its hold. You can run a razor utility knife between the glass and the wood to help break the bond. I have done this many times without breaking the stop, but sometimes it happens, and when you replace the glass you simply put back the pieces. If your window is less than 10 years old and clad with aluminum, you will have to replace the glass from the outside instead of as per above. The aluminum cladding can be carefully removed and replaced later. The new window will have the stop on the outside again sealed with butyl. Just be patient and it is not hard to remove. Your replacement glass size will be some even number less 1/8" (i.e. 23 7/8" x 47 7/8") and single-strength thickness.