Alternative Construction Research Guide - GCCDS

7 .2 | SheathingSheathingOverview: Sheathing is a material used to tie a building’sstructural framework together, creating a structuraldiaphragm that resists horizontal forces against the wall.Typical sheathing materials are 4’x8’ sheets of plywood orOSB (oriented strand board), although sheets with 9’ and10’ lengths are also available for higher ceilings. Sheathingis an essential component of construction.In hurricane-prone areas, alternative sheathing materialsinclude full-height OSB and sheets with pre-affixedweather barriers. Older homes along the Gulf Coast mayhave horizontal or diagonal sheathing made of dimensionallumber.(Fig. 11) Plywood and OSB can be purchased at almost every buildingsupply retailer and can be delivered on a trailer.INSTALLATIONConstruction Process: Sheathing is nailed to studwalls, with a prescribed nail pattern engineered towithstand local wind loads. Generally, the exterior finishmaterials are affixed to the sheathing, with a vapor barrierbetween them, such as Tyvec Housewrap or felt paper.Joints should be appropriately spaced at 1/8” or as definedby local code.Speed of Construction: The process of sheathing isfairly swift once the framing is complete. An experiencedcrew can sheath a one-story house in a day. Sheathingcan be further expedite by using full-height materials.Delivery Method: Plywood and OSB can be purchasedat almost every building supply retailer and can bedelivered on a trailer. Boards should be kept flat to reducewarping before installation.Required Equipment: Hammers and nails or nailguns, circular saw.Specialized Labor: Aside from basic carpentry knowledge,no specialized labor is needed.(Fig. 12) Aside from basic carpentry knowledge, no specialized labor isneeded for sheathing a house.