UNIT 31 Structural Wall Sheathing

Sheathing Inner layer of the outside wall Not part of the wall framing Structural part of the home Insulated sheathing requires diagonal bracing Requires corner bracing Can be applied when the: Roof has been framed Wall is completely framed and lying on the subfloor Wall frames have been erected, plumbed, and braced

Types of Sheathing Wood Edge types Shiplap Square Needed for butt joinery Dressed and matched Tongue and groove Should be applied horizontally or diagonally

Types of Sheathing Plywood Adds great strength and rigidity Twice as strong as walls sheathed with diagonal boards Applied horizontally or vertically (usually vertically) Comes in 4’ x 8’ sheets…..or longer in length Minimum of 5/16” thick

Types of Sheathing Gypsum Consists of two layers of lightweight paper with gypsum filler Comes in 2’ X 8’ sheets Should be applied horizontally Nailed in place with 1-3/4” to 2” galvanized roofing nails

Types of Sheathing OSB O riented S trand B oard Replaces plywood

Sheathing Carpenters prefer to add sheathing as soon as possible because…………. Scaffolding is available for roof framing The structure is more rigid There is a more solid structure for the ceiling and roof

Sheathing materials Building paper Applied between the sheathing and siding Should be water resistant but not vapor resistant Should be applied horizontally House wraps Made of fibrous plastic Allows water vapor to pass through Very durable, not easily torn