Racking – Roofing application method in which shingle courses are applied vertically up the roof, rather than across and up. Not a recommended procedure.

Radiant Heat Barrier – A silver foil blanket used in place of or in conjunction with other insulation. Does not have a R-value. Reflects heat back into the building in winter, and reflects the heat away in the summer.

Radiant Heating – Electric heating elements are enclosed in the ceiling panels; a separate thermostat controls each area or room.

Rafter – Structural member that supports a roof. Trusses have to a great extent taken over the job rafters used to do.

Rake – The inclined edge of a slope roof over a wall. (The edge above the gutter)

Reinforcing – To make stronger, usually refers to Rebar (steel rods) or mesh used in concrete slabs, columns or beans.

Release Tape – Plastic or paper strip is applied to the back of self-seeking shingles. This strip prevents the shingles from sticking together in the bundles, and need not be removed for application.

Retaining Wall – Wall that supports or holds back landscaping or earthworks on a hill. Wall is often made of poured concrete, interlocking block, or railroad ties.

Reversed Polarity – Usually noted on outlets, indicates that the hot and the neutral wires have been reversed (connected to the wrong terminals)

Ridge – The line or top of the roof, the peak, where the roof is divided, one side from the other. – the uppermost, horizontal external angle formed by the intersection of two sloping roof planes.

Ridge Beam – Structural member running the length of the Ridge supporting the upper ends of the rafters, not used with trusses. Commonly a 2X6.

Roof Space – Attic area, or area between a dwarf partition and sloping roof.

Roll Roofing – Asphalt roofing material similar to shingles but on a roll 36 inches wide.

Roof Sheathing – Wood covering the roof, under the shingles. Usually OSB board..

Romex – Romex wire is the standard type of wiring used inside homes today, recognizable by its off-white color plastic exterior. Roof Deck – See decking.