Holow-Core Slab
A precast concrete structural slab that uses internal cavities to reduce its weight.
Hip Roof
A roof that rises by inclined planes from all four sides of a building. A roof consisting of four sloping planes that intersect forming a pyramidal shape.
Hollow Concrete Masonry
Concrete masonry units that have open cores.
Homogeneous Material
Homogeneous Material is a uniform solid, liquid, or gas composed of one or more substances that cannot be mechanically disjointed, in principle. It may be a chemical formulation or compound; of undefinable composition (UVCB); or a combination of the two. Coatings and finishes such as plating, powder coats, enamels, etc. are considered unique homogeneous materials. https://healthymaterialslab.org/tool-guides/hml-resources
Hollow-Core Door
A door with face veneers on the outer surfaces, wood spacers around the edges, and a hollow interior supported with a honey-comb grid.
Home run (electrical)
The electrical cable that carries power from the main circuit breaker panel to the first electrical box, plug, or switch in the circuit.
Hollow Brick
A clay masonry unit whose net cross sectional area in the plane of the bearing surface is not less than 60 percent of the gross cross sectional area of that face.
Honey combs
The appearance concrete makes when rocks in the concrete are visible and where there are void areas in the foundation wall, especially around concrete foundation windows.
Hollow Clay Masonry
A unit whose core area is 25 to 40 percent of the gross cross-sectional area of the unit.
Hoistway, Elevator
A fire-resistant vertical shaft in which the elevator moves.
Horizontal Sheer
The tendency of the top wood fibers to move horizontally in relationship to the bottom fibers.
Humidity
The amount of water vapor withing a given space.
Humidifier
An appliance normally attached to the furnace, or portable unit device designed to increase the humidity within a room or a house by means of the discharge of water vapor. A device used to add moisture to the air.
Hurricane clip
Metal straps that are nailed and secure the roof rafters and trusses to the top horizontal wall plate. Sometimes called a Teco clip.
Honeycomb
Any substance having cells suggesting a mass of cells such as those built by the honeybee. Some hollow-core doors use the honeycomb principle in their construction.
Hot Melt
Adhesives that bond when they are heated to a liquid form.
HUD
Housing and Urban Development, federal agency.
Hose bib
- An exterior water faucet (sill cock).
HUD Mobile Home Standards
Officially, the National Mobile Home Construction and Safety Standards Act of 1974 for construction of mobile homes. Includes the following agencies: DAPIA Design Approval Primary Inspection Agency and IPIA Production Inspection Primary Inspection Agency.
Hot wire
The wire that carries electrical energy to a receptacle or other device in contrast to a neutral, which carries electricity away again. Normally the black wire. Also see ground.