Over the last several years our company has noticed a dramatic increase in silicon residue on new glass installations, especially on first time cleans at a new home.We believe it is quality control issue right from the manufacturer of the window. Soap and water or pure water window cleaning will not remove silicon,as special scrubbers and chemicals are required to remove silicon from glass. We can and have removed this, but a a considerable price increase for the customer. If you are replacing windows in your home, or are buying a new home we suggest the following: insist your home builder ensure window installers are installing windows free of silicon staining or check your self the windows and refuse to accept silicon stained windows. This appears to be a quality control problem/issue from the manufacturer. Do Not make it your problem!
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