Why does proper installation matter more than the window itself?

Even the best window will leak air, let in water, and underperform if it is installed poorly. Correct installation means the window is level, square, fully sealed, and properly insulated around the frame, which is exactly where cheap installs cut corners. In Chicagoland’s freeze-and-thaw climate, a bad install shows up fast as drafts, condensation, and rot. This is the heart of The McCann Way: senior crews who treat your home like their own and get it right the first time.