This letter is used when defining thermal resistance

Material used to enclose the horizontal underside of an eave, cornice, or overhang. Some panels may also be used as vertical siding.

Area where two adjoining sloped roof planes intersect on a roof creating a "V" shaped depression.

A composite of three windows, usually made up of a large center fixed unit and two flanking units at 30-,45- or 90- degree angles to the wall

A small hole in the bottom butt edge of the vinyl siding panel, allowing condensation to escape. .

A small window that fits over the top of a door or window, primarily for additional light and aesthetic value

This term is used to describe the amount of moisture that can pass through a wall surface

A method of constructing windows in which muntins are affixed to the inside and outside of a panel of insulating glass to simulate the look of true divided light.

A manufacturing component of vinyl or aluminum siding systems which have a curved channel that the planks fit into, used around windows and doors to make a weathertight seal.

On a double-hung window, the bottom rail of the upper sash and the upper rail of the lower sash, where the lock is mounted.

A style in which a narrow strip of siding appears to cover the seam between two wider boards. Usually siding is installed vertically