Weatherstripping for double-hung and casement windows comes in several forms. The right type to use depends on the type of window and the situation.

Spring-type weatherstripping is made from bronze, aluminum, stainless steel, or vinyl. The angled or V-shaped strips are the best kind of weatherstripping to use for double-hung windows because they seal well and are less visible than other types. The weatherstripping is nailed to the window frame except at the bottom, where it is nailed to the sash.

Pliable-gasket weatherstripping is made of a springy material such as vinyl, foam, felt, or sponge. Installed in the channels and sash, it is most effective for wood casement, hinged, and sliding windows.