I installed several Semco Windows in my home, to replace the original windows. I have to say that their performance has been outstanding. Further, I have a huge Bay Window with absolutely no overhang and they have never leaked after several years of being exposed to some fierce Northern California rains! Also, I have installed Semco casement windows, double-hung windows, and doors in several other homes, and I have yet to have had a call back for any reason. Properly installed, I am convinced that this window will not leak and that it is one of the finest high quality windows on the market! These windows are a terrific value!