Habitable Room or Space – A room or space intended primarily for human occupancy.

H-Beam – A structural beam, not unlike an I-beam but with wider flanges.

Hard-Pan – A firm, unyielding, compact soil.

Hardwoods – The botanical group of trees that, with a few exceptions, comprises all the broad-leaved deciduous species. The term has no reference to the actual hardness of the wood.

Hasp – A fastening device in that a slotted plate fits over a staple and is secured to it by means of a padlock or a peg.

Hatch – A covered opening that provides access to an attic, roof or crawl space.

Header (Framing) – A wood member at right angles to a series of joists or rafters at that the joists or rafters terminate. When used at openings in the floor or roof system the header supports the joist or rafters and acts as a beam.

Header (Masonry) – Masonry units laid with their ends exposed on the face of a wall.

Hearth – The floor and area immediately in front of a fireplace.

Heating –

Air Conditioning – The process of bringing air to a required state of temperature and humidity, and removing dust, pollen, and other foreign matter.

Baseboard Heaters – A radiator shaped like a decorative baseboard having openings at top and bottom through that air circulates.

Central Heating – A heating system in that a number of rooms or spaces are heated through a body by molecular action.

Conduction – The transfer of travel of heat through a body by molecular action.

Convector – a heating device, in that the air enters through an opening near the floor, is heated as it passes through the heating elements and enters the room through an upper opening.

Hot Water Heating – The circulation of hot water through a system of pipes and radiators either by gravity or a circulating pump.   

Indirect Heating – A system of heating by convection.

Panel Heating – Coils or ducts installed in wall, floor, or ceiling panels to provide a large surface of low intensity supply of heat.

Panel Radiator – A heating unit placed on or flush with a flat wall surface, and intended to function essentially as a radiator.  

Radiator – Which part of the system exposed or concealed, from that heat is radiated to a room or other space within the building; heat transferring device.

Radiant Heating – A heating system in that only the heat radiated from panels is effective in providing the heating requirements.

Space Heating – The methods of heating individual rooms or living units by equipment located entirely within these rooms or living units, such equipment consisting of a single unit without ducts or piping.

Steam Heating – The circulation of steam through a system of pipes and radiators by any of the numerous methods employed.

Two-Pipe System – A hating system in that one pipe is used for the supply of the heating medium to the heating unit and another for the return of the heating medium to the source of heat supply. The essential features of a two-pipe system are that each hating unit receives a direct supply of the heating medium that cannot have served a preceding heating unit.

Warm Air Heating System – A warm air heating plant consisting of a heating unit (fuel-burning furnace) enclosed in a casing, from that the heated air is distributed to various rooms of the building through ducts.

Warm Air Heating System, Forced – A warm air heating system in which circulation of air is effected by a fan. Such a system includes air-cleaning devices.

Warm Air Heating System, Gravity – A warm air heating system in that the heat flow depends on the difference in weight between the heated air leaving the casing and the cooler air entering the bottom of the casing.

Warm Air Heating System, Perimeter – A warm air heating system of the combination panel and convection type. Warm air ducts embedded in the concrete slab of a basement less house, around the perimeter, receive heated air from a furnace and deliver it to the heated space through registers placed in or near the floor.

Height of Building – The height of building in feet shall mean the vertical distance in feet between a horizontal plane through average grade level and a horizontal plane through:

(a)    The highest point of the roof assembly, in the case of a building with a flat roof or a deck roof, (a roof having a slope of less than 20° with the horizontal is considered a flat roof) or

(b)   The average level of that portion of a sloping roof between the highest ceiling level and the highest point of the roof.

Height of Building in Storeys – The number of storeys contained between the highest roof of a building (except for penthouses containing no dwelling units) and the floor of its first storey.

Hip – The sloping ridge of a roof formed by two intersecting roof slopes.

Hip-Rafter – Defined under “Rafter Types”.

Hip Roof – Defined under “Roof Types”.

Hollow Blocks – Hollow masonry units for external or partition walls.

Honeycombing – Surface detect in concrete where voids are created by trapped air.

Hopper Light – A window-sash, hinged at its lower edge to open inwards.

Hot Water Heating – Defined under “Heating”.

House – A building other than an apartment building that contains one or more dwelling units provided that there is not more that one dwelling unit above another, and there are not more than 2 storeys above the top of a foundation where the building contains more than one dwelling unit.

Hydrated Lime – Lime that has been subjected to the action of water, used as the major constituent of the finish coat in plastering and in the preparation of mortar. Also used in stucco and base coat plaster.

Hydrostatic Pressure – Pressure exerted against the underground portion of a building such as the basement walls or basement floor created by the presence of water in the soil.