A window unit that has two operable sashes which move vertically in the frame.
A window consisting of two sashes of glass operating in a rectangular frame, both the upper and lower halves can be slid up and down and usually use a counter balance mechanism to hold the sash in place.
Two-sash window in which one or both sashes slide up and down.
More traditional in appearance than casement windows. They come in larger widths (up to 45") and are a good choice to maximize the amount of wood on the interior of a home.