Should I close my windows before window cleaning?

Solution put on a pane does not stay where it lands. Water and cleaning solution applied to the outside of the glass run down the surface and onto the frame beneath it, and NGA's exterior procedure starts at the top of a building and continues to the lower levels to reduce the risk of leaving residue and cleaning solution on glass that has already been cleaned.

The bottom of that path is the frame, and a sash or slider left open is an opening in it. No published standard tells a homeowner to close a window before cleaning; the reason is the path the water takes, not a rule a maker wrote down. Solution that lands past the surface it was meant for is the overspray question, which on a roof job is its own subject in how soft washing works around a house.

The PGT, CGI and WinDoor care instructions tell owners of those products to clean and rinse each window or door individually, to prevent cleaning agents from permeating for long periods of time. NGA's routine method has its own sequence: the glass is soaked with clean water and a mild, non-abrasive solution, and immediately afterward a window cleaning squeegee removes all of the solution from the glass.

Among NGA's own DO NOT items is allowing water or cleaning residue to remain on the glass or adjacent materials, and a frame sits right next to the glass. The published method for exterior glass sets out the whole routine. NGA's steps do not mention open windows; what an open sash changes is where solution running down the frame can go next.

The PGT, CGI and WinDoor maintenance list gives owners of those products an item of their own: routinely inspect and clean the water drainage, the weep systems, to maintain proper drainage. NGA adds that the presence of weep holes is recommended but is not sufficient to overcome the risk of improper cleaning materials coming in contact with the edge of glass products. Frames, drainage and how often coastal glass needs cleaning carries the maker's homeowner items in full.

What cleaning agents reaching a glazing pocket can do to a sealed unit is answered at can window cleaning hurt the window seals, and a mark running down from a frame at why windows have drip lines under the frames. Whether a pane is reached by ladder or by pole is its own question, at do window cleaners use ladders, and what exterior cleaning reaches and what it does not is answered at is exterior window cleaning enough.