Building Construction Flashcards
(32 cards)
What is a beam
Types of beams
Transmits forces in a direction perpendicular tsuch forces to the reaction points (point of support)
Joist -wooden beam
Girder - anyt beam, of any material which supports be
What is a column
Conventional vs Lightweight construction
Conventional
-2x6 or larger - obtain structural strength from size
Lightweight
- truss can span up to 70’
- Uses geometry with compression and tension
Gable Roof - Conventional vs lightweight
Conventional
- Ridgeboard and rafters are seperate from ceiling joists
- if collapse occurs rafters may just fall onto joists
Lightweight
- The rafters are the top chord of truss
- The joists are the bottom chord of truss
Common Roof Types
Gable
hip
Flat
Bridge Truss
Arch
Sawtooth
What type of roof
Gable
What type of Roof
Gable
Gable Roof construction
- roof construction
- rafter size and spacing (conventional)
A frame -Conventional or Ordinary
Conventional - Ridge board pluse rafters extending down to and across outside walls.
On a Gable Roof what other supports are used
Collar beam - runs perpendicular rafter to rafter
Ceiling joist
Gusset Plate gauge and pronge length
18 gauge steel plates
3/8” prongs
What is the common rafter spacing for a trussed roof
48” OC
Common Roof Coverings
-supported by
shake, tile, rock,
skip sheathing or 1/2 inch plywood or OSB
what is a purlin
Structural members that support rafters
- in panalized construction spaced 8’ apart and are system from which panel will be hung.
- Runs perpendicular to beams
- Conventional construction made of lumber in lightweight made of truss systems
Panalized Construction
- Typical material of panel
- Rafter size and orientation
- How are rafters attached
OSB or Plywood panel 4’x8’
Rafters 2x4 or 2x6 - rafters are hung on metal hangers from perlins
rafters run perpendicular to perlin and parallel to beams
What is a scupper
A drainage device in the form of an outlet through a wall
What is a ledger
Horizontal support piece normally used to supports the ends of a structural member
-typically purlins will be hung to ledger wall-typically long side of building
Scuppers ofter hung on ledger wall
What type of roof
Panalized Roof
Perlins attached with hangers to what looks like a glue lam beam
Rafteers 2x4 with osb on top
Purlins 8’ spacing
Beams are supported by pilasters (can be steel post, or saddle.
4 Components of a flat panalized roof
Beams (lam wood or metal)
Purlins
2x4 joists
1/2” plywood decking
Flat Panelized - Beams
- common dimension
- how supported
- length
- space between
6” x 36” common
supportted by pilasters, wood or steel posts, or saddles
-Beams may be bolted together to provide lengths in excess of 100’
Spaced 12 to 40 feet apart
Flat Panelized - Purlins
Common size
Spaced
Use of skylights
4x12 common
spaced 8’ apart
skylight can dictate purlin direction
Trusses can substitute conventional purlins
Flat Panalized - Joists
Size
Installation
Spacing
2x4
Installed with metal hanger
2’ OC
Common Flat Panelized Decking
4x8 plywood covered with comp roof material
3 layers of insulation paper stapled to underside
Tar impregnated kraft paper covered by thin aluminum foil.
