01 May 1999
9,000 meter length of the filament.
NOTE: Cure may be accomplished, for
example, by removal of solvent or
thickness of a roof system upon which a given
moisture survey method is effective.
Design loads--The "live load" (i.e. super-
imposed loads) that a structure is designed to
resist (with appropriate safety factor) plus "dead
characterized by a continuous, open longitudinal
load" (i.e., weight of permanent loads).
seal with top felt rolled back from underlying felt.
Dew point--The temperature at which water
Cutback--Solvent-thinned bitumen used in cold
vapor starts to condense in cooling air at the
process roofing adhesives, flashing cements,
existing atmospheric pressure and vapor
and roof coatings.
Cutoff--A detail designed to prevent lateral
Double pour--Doubling of flood-coat, graveling-
water movement into the insulation where the
in operation, to provide additional waterproofing
membrane terminates at the end of a day's
integrity for a BUR membrane.
work, or used to isolate sections of the roofing
system, usually removed before the continuation
Downspout--A conduit used to carry water from
of the work.
the gutter of a building to the ground or storm
Dampproofing--Treatment of a surface or
structure to resist the passage of water in the
Dry (n.)--A material that contains no more water
absence of hydrostatic pressure.
slope. (See Slope)
Duckboard--A boardwalk or slatted flooring laid
on a wet, muddy or cold surface.
Dead level asphalt--A roofing asphalt
conforming to the requirements of Specification
Eave--The line along the sidewall formed by the
D312, Type I.
intersection of the planes of the roof and wall.
Deck--The structural surface to which the
Eave height--The vertical
roofing or waterproofing system (including
finished floor to the eave.
insulation) is applied.
Edge stripping--Application of felt strips cut to
Degree-days--The difference between a
narrower widths than the normal felt roll width to
reference temperature (usually 180C [650F]) and
cover a joint between flashing and built-up
the mean temperature for the day times 24
hours times the number of days in the period.
Degree-days are used to compare the severity
Edge venting--The practice of providing
of cold or heat during the heating or cooling
regularly spaced protected openings at a roof
perimeter to relieve water vapor pressure in the
insulation. (It is of doubtful efficacy.)
Delamination--Separation of the plies in a
membrane or separation of insulation layers
Efflorescence--A deposit or encrustation of
soluble salts, generally white and most
commonly consisting of calcium sulfate, that
Denier--A unit used in the textile industry to
may form on the surface of stone, brick,
indicate the fineness of continuous filaments.
concrete, or mortar when moisture moves
Fineness in deniers equals the mass in grams of
through and evaporates on the masonry. Often