Exterior Walls (Wood)

Framing Techniques in Light Frame Construction General Terms & Methodology Platform Framing Balloon Framing Post & Beam

Forces on Exterior Wall Construction Wall had their own dead load Walls support vertical loads (LL + DL) from roof ceiling floors Must also resist lateral forces due to Wind Earthquake (seismic)

Wind--Horizontal/Lateral Load Palm tree pierced by plywood missile, Hurricane Andrew Wind causes both horizontal & vertical movement with vertical forces called uplift Use of wind speed map to determine wind speed (70 to 110 miles per hour)

Wind Forces Horizontal forces are treated like seismic Sucking force Lifting Horizontal forces are treated like seismic Vertical forces are called uplift Wind blowing across the structure creates a negative pressure (sucking force) Wind blowing thru an opening increases inside pressure (lifting force)

Earthquakes Shock waves cause lateral and vertical motion in a building Usual design, for vertical forces, will take care of the vertical seismic forces Major factors effecting seismic forces: The type of structure (material its made of) Nature of soil under the building Building are not designed to be earthquake-proof, but to be earthquake resistant

Exposed Earthquake Module Connections called “ductile” are designed to give the building the ability to move, bend or stretch without snap and breaking apart during earthquakes

Typical Wall Construction One and two story framing 2” x 4” @ 16” O.C. Occasionally 2” x 6” @ 24” O.C. Three story framing(load bearing walls) lower floor = 2” x 6” @ 16” O.C. other floors = 2” x 4” @ 16” O.C.

Window Framing Terms Header Header Jack Cripple Studs Double Plate Rough Sill Trimmer Window Framing Terms Header supports structure above windows Header Jack supports header Cripple Studs Double Plate Rough Sill Trimmer additional stud to trim out window

Platform Framing Also called Western Framing Subfloor is Platform Rafter or Truss Subfloor is Platform Also called Western Framing Blocking Double Plate Sway Bracing (cornerbracing) Girder Ledger Floor Joist Sill (Mud Sill) Foundation Sheathing

Balloon Framing Studs extend from sill to roof line (full length) Also called Eastern Framing Terms similar to Platform Framing

Balloon Framing Used primarily for 2 story construction Less chance of shrinkage or movement recommended for masonry veneer & stucco 2nd floor supported by wall with let-in 1x4 called a ribbon Less overall material Longer members usually more costly Firestop blocking required

Balloon Framing Terms Ribbon Firestop

Framing Construction at Corners 3 full studs good with super insulated buildings 3 full studs and blocking 3 full studs and 1/2” shim

Post & Beam Relatively new and less common in residential construction T&G planks 2x6 or 2x8 Relatively new and less common in residential construction Used in heavy timber const for years post Beam and Post typically 4’-8’ OC

Tongue & Groove Planking Used for Roof or Floor when structure is space 24” or more O.C.

Shear Wall Design Resistance to lateral forces resulting from earthquakes or wind Connections: 1 sheathing to joist 2 joist to top wall 3 edge nailing 4 tie-down straps 5 anchor/shear bolts

Detailing areas of Shear Walls Diaphragm transfer Detailing areas of Shear Walls

Exterior Finishes Siding Stucco Wood Siding Metal Siding Steel Aluminum Vinyl Siding Stucco Exterior Finish System--a nylon mesh & plaster over insulation board

Wood Siding Various sizes and Shapes Solid wood T1-11 (plywood) 4’x8’ sheets Masonnite Lap board 8-12” x 16’

Steel & Vinyl Siding Higher in Cost Lower in Maintenance Long lasting no painting Long lasting Concerns when using this siding expansion denting cracking rusting

Cement Stucco } 7/8” sheathing vs. open frame Least expensive building paper wire fabric lath furring nails drip screed 3 coats of plaster finish } 7/8” brown scratch

Interior Finishes Plaster & Lath Wood Paneling Dry wall

Plaster & Lath Old technique - not in common use today 3/8” - 1/2” thick lath 1/2” coat plaster uses a ground board at edges

Wood Paneling 4’ x 8’ sheet panels vertical/horizontal/angle pieces solid boards wide range of wood types and colors

Drywall Commonly called sheet rock, gypsum board (GB), or plaster board typically 1/2” on wall, 5/8” on ceiling Nail directly to studs, nails commonly 8” OC Tape - 3 coats/ texture Green/blue board or cement board for bathrooms

Assignment Sheet A-4 Dimension the enlarged entry plan Add restrooms to match A-1 & A-2 Reference door and window (A-1 & A-2) Hatch or poche’ as needed Using elevation 1/A-4 create elevations for A/A-4 and B/A-4

Drawing Assignment Wall Section 5/8”dia x 12”AB @ 32” 8” Min from backfill to top FDN 4” concrete slab w/ 6x6 10/10 wwf or wwm (wire welded fabric or mess) Blocking 6-8”compact fill 95% density foundation wall 8” with normal footing size (w x 2w) 30” frost depth Foundation insulation

Drawing Assignment Wall Section Cont. 2”x4” wood studs Treated wood plate Found. (2) #5 bars top and bottom and (1) #5 @ 18” o.c. vertical 12”x18” cont. conc. footing w/ (2) #4 bars x cont. #4 ties @ 18” o.c. (50% 2’-6” & 50% 1’-6”) T&G plywood subfloor (second level)

Wall Section Drawing Cont. Slope 3:12 5/8” GB inside wall Beam bearing @ 8’-0” Roof beam 3x10 3/4” CDX plywood sheathing 3/4” T1-11 siding (brick, stucco, etc.) Overhang 18” 2x2 starter board 1-1/2” from edge