Roofing Terminology
(Click on a letter to learn more)
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
R-Value
The resistance to heat transfer of a material.
Rake
The sloped edge of a roof at the first or last rafter.
Reflectivity
The ability of the surface of a material to reflect the infra red energy of a light source.
Reglet
A groove in a wall or other surface adjoining a roof surface for use in the attachment of counterflashing.
Reinforced Membrane
A roofing or waterproofing membrane reinforced with felts, mats, fabrics, or chopped fibers.
Relative Humidity (RH)
The ratio of the weight of moisture in a given volume of air vapor mixture to the saturated (maximum) weight of water vapor at the same temperature, expressed as a percentage. For example, if the weight of the moist air is 1 pound and if the air could hold 2 pound of water vapor at a given temperature, the relative humidity (RH) is 50 percent.
Re-Roofing
The practice or applying new roofing material over existing roofing materials.
Ridging
An upward, "tenting" displacement of a roof membrane, frequently occurring over insulation joints, deck joints and base sheet edges. Generally associated with improper application.
Roll Roofing
The term applied to smooth surfaced or mineral surfaced coated felts.
Roof Assembly
An assembly of interacting roof components (including the roof deck) designed to weatherproof and, normally, to insulate a building's top surface.
Roof System
A system of interacting roof components (not including the roof deck) designated to weatherproof and, normally, to insulate a building's top surface.
Rubber
A polymeric material, which, at room temperature, is capable of recovering substantially in shape and size after removal of force.
Back to Chapple Brothers Main Page