Aluminum Window Fitting Tolerance in Brick Walls: Why Cracks Start at the Gap
The Gap Is the Real Structural Detail Brick-wall window cracks usually start long before the first screw goes in. The failure begins when a rigid aluminum frame is treated like it can simply be pushed into masonry and made to fit by force. Brickwork is uneven, mortar joints age at different rates, and aluminum moves with temperature. The narrow perimeter gap between the two is not leftover space. It is the part of the assembly that prevents the wall from being asked to absorb movement it was never meant to take. ...