Humidity, Absolute - the weight of water vapor per unit volume.
Humidity, Relative - the ratio of water vapor present in air to the water vapor present in saturated air
at the same temperature and pressure.
Hypalon - a chlorosulfonated polyethylene synthetic that has been used as a base for making
Insulation - a material used in building construction to retard the flow of heat through the enclosure.
It is made from a variety of organic and inorganic fibers and foams, e.g., expanded/extruded
polystyrene, glass fiber, cellular glass, phenolic foam, perlite, polyurethane foam, polyisocyanurate
foam. It can be loose-filled, or used in batt, board, or block form..
Isolation Joint - a formed or assembled joint specifically intended to separate and prevent the
bonding of one element of a structure to another and having little or no transference of movement
or vibration across the joint.
Jamb - the side of a window, door opening, or frame.
Joint - the space or opening between two or more adjoining surfaces.
Lap Joint - a joint in which the component parts overlap so that the sealant or adhesive is placed
into shear action.
Latex - a colloidal dispersion of a rubber resin (synthetic or natural) in water, which coagulates on
exposure to air.
Latex Caulks - a caulking material made using latex as the raw material. The most common latex
caulks are polyvinyl acetate or vinyl acrylic.
Latex Sealant - a compound that cures primarily through water evaporation.
Lock-strip Gasket - a gasket in which sealing pressure is attained by inserting a keyed locking strip
into a mating keyed groove in one face of the gasket.
Masonry - construction, usually set in mortar, of natural building stone or manufactured units such
as brick, concrete block, adobe, glass block, tile, manufactured stone, or gypsum block.
Mastic - a thick, pasty coating.
Mechanical Connection - a joining of two or more elements by means of mechanical fasteners, such
as screws, bolts, or rivets but not by welding or adhesive bonding.
Metal Building System - a complete integrated set of mutually dependent components and
assemblies that form a building including primary and secondary framing, covering and
accessories, and are manufactured to permit inspection on site prior to assembly or erection.
Mullion - external structural member in a curtain-wall building. Usually vertical. May be placed
between two opaque panels, between two window frames, or between a panel and a window frame.
Open Cell - a cell not totally enclosed by its walls and hence interconnecting with other cells.