purlin

Rafter-supporting timber

A purlin is a horizontal beam in a roof structure, running parallel to the ridge and supporting the rafters or roof decking.

Purlins span between the principal rafters or trusses, transferring the roof's weight to the main structural supports: The carpenters installed purlins before laying the metal roofing panels.

structure

rafter

Sloped roof support

joistHorizontal structural beam
trussLoad-bearing beam arrangement
girderMain structural support beam

girt · batten · cleat · stringer · wall plate · brace · strut · kingpost · timber frame · steel frame

roofing

eaves

Projecting roof edges

ridgeNarrow raised strip
sheathingProtective outer layer
claddingOuter protective layer

underlayment · flashing · fascia · soffit · gable · hip · valley · dormer · roof pitch · sheeting

installation

spacing

Interval arrangement between objects

spanDistance between endpoints
bearingPosture or orientation
fastenerSecures things together

bracket · clamp · cleat · bridging · blocking · hanger · anchor · bolt · screw · weld

Categories

Steel Partssteel beam, I-beam, girder, rivet, bolt
structural elementsgirder, beam, column, truss, brace
structural supportsbeams, posts, columns, scaffold, girders
timber framingtimber frame, exposed beams, timber framing, wooden beams, timber joints
wood partsboard, plank, beam, post, rail
roof framingrafter, ceiling joist, roof truss, truss, king post

Opposites

structural orientation

purlinpost

Vertical structural beam

rafter · column · stud · king post

structural location

purlinjoist

Horizontal structural beam

floor joist · ceiling joist · beam · girder · mudsill

roof framing hierarchy

purlinrafter

Sloped roof support

joist · roof truss

Family

Familiarity: Top 1,000,000
Profile: Used worldwide · Timeless · Concrete · Rated G