01 May 1999
through a stated thickness of material with a
type of fabric reinforcement. Values are reported
stated temperature differential Btu/h.ft20F
in stress, e.g., pounds, or stress per unit of
thickness, e.g., pounds per inch.
Thermal insulation--A material designed to
Tearoff--Removal of a failed roof system down
reduce the conductive heat flow.
to the structural deck surface.
Tee joint--the condition created by the
overlapping intersection of three or four sheets
in the membrane.
Thermal shock--Stress-producing phenomenon
resulting from sudden temperature drops in a
roof membrane--when, for example, a rain
shower follows brilliant sunshine.
Thermogram--A visible light record of the
display of an infrared camera system via a
Polaroid print, 35 mm film, or videotape.
Thermography--A technique for producing heat
pictures from the invisible radiant energy emitted
from stationary or moving objects at any
Tensile strength--(1) The maximum tensile
temperature of the objects under view. The
stress per unit of original cross sectional area
electronic generation and display of a visible
applied during stretching of a specimen to break;
units: SI-metric--Megapascal or kilopascal,
customary--pound per square inch; (2) The
Thermoplastic--Capable of being repeatedly
longitudinal pulling stress a material can bear
softened by increase of temperature and
without tearing apart; (3) The ratio of maximum
hardened by decrease in temperature. The
load to original cross-sectional area. Also called
thermoplastic form allows for easier seaming
both in the factory and in the field.
Tensile test--A test in which a specimen is
Thermoplastic elastomers--Polymers capable of
subjected to increasing longitudinal pulling
remelt, but exhibiting elastomeric properties;
related to elasticized polyolefins. They have a
limited upper temperature service range.
Therm--A unit of heat commonly used by
utilities, equivalent to 100,000 BTU = 1.05 x 108
Thermoplastic resin--A material with a linear
macromolecular structure that will repeatedly
soften when heated and harden when cooled.
Thermal block--A spacer of low thermal
conductance material, designed to prevent
Thermoset--A material that will undergo (or has
formation of a thermal bridge.
undergone) a chemical reaction by the action of
heat, catalysts, ultraviolet light, etc., leading to a
Thermal bridge--Interruption of a layer of
relatively infusible state.
thermal insulation by a material of high thermal
membrane or material assembly extending
totally through a wall and its cavities, positioned
through a material whose surfaces have stated a
temperature differential Btuin./hft40F(W/m20C).
to direct any water within the wall to the exterior.
Toggle bolt--A two-piece assembly consisting of