Rafter

A primary beam member supported on columns.

Rake

The intersection of the plane of the roof and the plane of the gable.

Rake Trim

The sheeting item joining the roof and wall sheeting at the rake. Also called Gable Trim.

Reactions

The resisting forces, at the column bases of a frame, holding the frame in equilibrium under a given loading condition.

Revision

A change that is made to the building design, component details, location of accessories, etc.

Ridge

The peak, or highest point of a gabled building, which describes a horizontal line running the length of the building.

Ridge Flashing

Continuous metal flashing used to close roofing material along the ridge of a roof. Also called Ridge Cap or Peak Panel.

Ridge Connection

A connection, between two rafter members, which transfers the moment from one side of the connection to the other and maintains, under application of load, the same angle between the connected members that exists prior to the loading. See also Moment Connection.

Ridge Sign

The manufacturer’s sign at the peak or highest point of the gable. Also called Peak Sign.

Ridge Ventilator

The ventilator used at the ridgeline.

Rigid Frame

A structural frame consisting of members joined together with rigid (or moment) connections so as to render the frame stable with respect to imposed loads, without the need for bracing in its plane.

Rigid Frame Endwall

A system of endwall framing where the main interior frame is used at the endwall mostly for the purpose of future expansion.

Risers

The vertical rise of the steps of a staircase.

Roll-Up Door

A door, which opens vertically and is supported on a shaft or drum and runs along vertical tracks.

Roof Covering

The exterior roof skin consisting of panels or sheets, their attachments, and weather sealant.

Roof Curb

Weatherproof flashing used on roofs to support power ventilators or ducting. Roof Curbs can be fiberglass or sheet metal.

Roof Extension

An extension of the roof beyond the endwall and/or sidewall of a building.

Roof Monitor

Raised gable, or portion of the main building, located at the ridge, to allow lighting and ventilation.

Roof Slope

The angle that a roof surface makes with the horizontal. Usually expressed in units of vertical rise to 10 units of horizontal run.