Valley      The internal angle formed by the junction of two sloping sides of a roof.
Valley shield     An underlayment for added protection in the heavy water flow areas of a roof. This self-adhering product has a waterproof asphalt coating.
Vapor retarder     Any substance that prevents the transmission of water vapor.
Vault      An arched or domed structure.
Vaulted      Having an arched or dome shaped ceiling or roof
Veneer    A decorative application to a flat surface intended to simulate a full thickness of the material. Used commonly on paneling or wood surfaces where the surface underneath is of a lesser quality material.
Vent     Any outlet for air that protrudes through the roof deck, such as a pipe or stack. Any device installed on the roof, gable or soffit for the purpose of ventilating the underside of the roof deck.
Veranda     Covered porch or balcony
Vestibule      Covered and enclosed entry to a building
Voltage     A measure of electrical potential. Most residences are wired with 110 and 220-volt lines. The 110-volt power is used for lighting and most of the other circuits. The 220-volt circuit generally serves large appliances such as a stove or clothes dryer.The formula is watts divided by amps equals volts.