A mathematical representation of the frequency or ratio that specific wind speeds occur within a specified time interval.
Rays, wood
Strips of cells extending radially within a tree and varying in height from a few cells in some species to 4 inches or more in oak. The rays serve primarily to store food and transport it horizontally in the tree. On Quartersawn oak flooring, the rays form a conspicuous figure, sometimes referred to as Flecks.
Raze
To demolish.
Re-cover (overlay)
The installation of a new roof system over an existing system without removing an existing system.
Re-impregnate
To replace oils and bitumen in the components of the BURM which through weathering and oxidation, have been lost.
Re-roofing
The procedure of installing a new roof system.
Reactance
A counter voltage occurring in AC circuits causing power loss.
Reaction flux
A paste used in soldering that reacts chemically with the metal being soldered when heat is applied.