Wood Construction CTC375 Wood Lumber Any wood cut

Wood Construction CTC-375

Wood • Lumber – Any wood cut into a size and shape used as a building material – Timber – lumber with smallest dimension >5” – Board - <2” thick, at least 2” wide – Dimension - >2” thick, <5” thick, 2+” wide – Beam & stringer - >5” thick, 8”+ wide – Post & Beam – lumber approximately square • 5+” thick and wide

• Rough sawn lumber – Sawn on all four sides to a nominal thickness and width • Dressed lumber – Sanded on 1 -4 sides – Called by nominal size – Sanding takes ¼” off per side • Available in sizes from 8 – 16 feet – Studs also available at 92” – gives 8’ ceiling height

• Types of wood construction – Post & Beam • Wooden frame provides structural support • No interior bearing walls • Posts must be attached to foundation – Balloon Framing F 13 -4 • • Exterior walls are continuous from foundation to roof Floors are attached to the walls Revived in 1980’s as solar power gained popularity Need to place fire breaks in the walls

– Platform Framing F 13 -3 • • Walls rest on floors Floor is built to edge of foundation then sheathed Wall is built on top of floor Walls have single bottom plate and double top plate for strength • Fire blocks at every floor

• Panels or module construction – Structural Insulated Panels (SIP) • Can be walls or roof systems – Conventional floor system but walls are constructed off site in 4 x 8 panels and hauled to site – Allows for windows, doors to be installed at same time as walls – Must have a flat surface

Construction • Hurricane clips for roof • Anchor bolts and tie downs for foundationframe connections • Blocking – Where do you place blocking? • Joist Bridging – Makes floor into a system

Floor Systems – Conventional 2 x construction • • Box beam surrounds joists Girders are built up from 2 x stock Joists are 2 x stock 16” o. c. ¾” sheathing is glued and screwed onto joists – Can use 5/8” sheathing but total floor must = 1. 25” – Engineered Lumber • I-joists – 2 x 3 top & bottoms with OSB web – Long and strong – Can span 40 – 60 feet – eliminates interior bearing walls

• Floor Trusses – Usually used in commercial buildings • Provide long spans • Holes in Joists – Holes only in center of joist (neutral axis) and only within 1/3 of span of end – Diameter not more than 1/3 of height or be closer than 2” from an edge

Roof Trusses • Components – F 13 -12 – Truss types F 13 -13 – Erection F 13 -14 – Bracing F 13 -15

Timber Construction • F 13 -24 – Post and beam on a larger scale – Connections F 13 -25