I had a couple of visitors this morning: The president of Newtec windows and a technical expert from the manufacturer that supplies Newtec with the vinyl moldings.
I again got my smoke pen out so that we could take another look at the air leakage of the 1st floor casement windows. I didn’t need the smoke pen. I actually barely got to the window. My visitors took the window seat and carefully inspected the corners, with the windows closed and open.
We quickly agreed that the corners are the problem. We identified an increasing gap between frame and casement in the corner when the window is shut and locked.
The frame has a set of inner and outer gaskets. When the window is shut and locked, the casement is supposed to press into the gaskets, which would provide the specified air seal.
However, with the increasing gap in the corners, the gaskets and casement are not in full contact, thus the air leakage.
Very good. We have identified and agreed on what the problem is and that it needs to be fixed. My visitors took that information with them, and promised to get back to me in due course with a solution. I guess there are a couple of ways to go about it and I am really interested to hear how they plan to plug the gap. Stay tuned!