H

HARDNESS

HCFC
HEAT AGING

HEAT FLUX
HEAT SINK

HERS

HFC
HIDING POWER
HIGH PRESSURE SPF
HOLIDAYS
HOME ENERGY RATING SYSTEM (HERS)
HYBRID INSULATION
HYDROPHILIC
HYDROPHOBIC
HYGROSCOPIC
HYGROSCOPICITY

HARDNESS: Ability of a coating film, as distinct from its substrate, to resist cutting, indentation, or penetration by a hard object. 

HCFC: Hydrochlorofluorocarbon. A physical blowing agent containing at least one carbon, one fluorine, and one chlorine atom in its structure (e.g., HCFC-141b). Effective January 1, 2005, the United States Environmental Protection Administration (EPA) issued a Use Ban Regulation on HCFC-141b blowing agent, meaning that SPF systems containing HCFC-141b could not be domestically produced or imported, under penalty of law, after this date. The regulation also required that any existing inventory of finished product containing HCFC-141b could not be applied after June 30, 2005.

HEAT AGING: Controlled exposure of materials to elevated temperatures for a period of time. 

HEAT FLUX: The rate of heat transfer per unit area. Usually used to describe the rate of radiant heat transfer. Units are W/m2 (Btu/ft2•hr).

HEAT SINK: A cold substrate that absorbs the SPF exothermic heat, slowing down the reaction and/or rise of the polyurethane foam or coating. 

HERS: See HOME ENERGY RATING SYSTEM.

HFC: Hydrofluorocarbon. A physical blowing agent containing at least one carbon and one fluorine atom in its structure (for example, HFC-245fa). HFCs have no ozone depletion potential.

HIDING POWER: The ability of a coating to hide or obscure a surface to which it has been uniformly applied. 

HIGH PRESSURE SPF: See SPF, HIGH PRESSURE.

HOLIDAYS: Application defects whereby small areas are left uncoated. 

HOME ENERGY RATING SYSTEM (HERS): HERS is a rating system for residential energy efficiency developed by EnergyStar and RESNET (Residential Energy Services Network). Through a comprehensive design review and analysis, it incorporates HVAC, building enclosure; and orientation, as well as appliance and lighting selection. A HERS score of 0 indicates a net zero-energy home, while a HERS score of 100 represents the energy consumption of home built to the 2003 IECC model energy code. A maximum HERS score of 70 is required for a home to be EnergyStar compliant.

HYBRID INSULATION: A combination of insulation types typically arranged so the SPF insulation acts as an air barrier and/or a vapor retarder, and the other insulation type contributes by adding R-VALUE. (See also R-VALUE.)

HYDROPHILIC: Also known as “water-loving.” Having an affinity or an attraction for water; having the ability of uniting with or dissolving in water.

HYDROPHOBIC: Also known as “water-fearing.” Having no affinity for water; not compatible with water. 

HYGROSCOPIC: Attracting, absorbing, and retaining atmospheric moisture.