BUILDING CONSTRUCTION Flashcards
Gable Roof
Pitched roof with two sloped sides
Hip Roof
Pitched roof with 4 sloped sides
Mansard Roof
Roof with 4 sloping sides, break in the slope on all 4. May have a flat top
Gambrel Roof
Two slopes on each side, upper one being flatter than the lower slope
Sawtooth Roof
Vertical and sloping surfaces, resembles a
Lamella Arch
Arch constructed of short wooden members connected in a specific geometric patten, risk of collapse when 20% strength lost
Truss Roof
Strong roofing system composed of chords, diagonals, and gusset plates. Preassembled
Bowstring Truss Roof
Truss with a curved top chord
Arched Roof
Rounded roof usually associated with a bowstring truss
Rafters
2x4 to 2x14 spaced 12-24”, support roof decking. Outward force pushes on exterior wall creating tension
Type I Class
Fire Resistive
Type III Class
Exterior Protected, masonry
Type II Class
Noncombustible
Type IV Class
Heavy Timber
Type V Class
Wood Frame
Panelized Roof
Beams, Purlins, Joists, Plywood decking
LamBeams spanning length or width of building, spaced 12-40 feet
Gusset plates beginning to substitute purlins, metal hangers
Joists 24” on center
Conventional Roof
Wood rafters, 2x6 or larger, across outside walls. Supported with pilasters for strength
Older roofs may have scissor bracing (bridging)
Lightweight Panelized Roof
Large prefab panels, made from plywood or OSB, assembled on the ground and lifted into place. Supporting structures are lighter materials (GLU LAM) beams.
Lightweight Construction
Lack of mass (2x4 trusses)
Suspect connections (gusset plates, hurricane clips, roof clips)
Sheeting materials (OSB)
Gets strength from tension/compression (truss)
Age of building (new)
Conventional Construction
Larger mass (2x6,8,10,12 rafters)
Full span of lumber between load bearing walls (2x8/10/12 floor joists that carry to beams) (beams rest on columns which transfer load to footers)
Sheeting materials (1x6, plywood)
Age of building (old)
