scope:

With any building material or product, sound construction and installation practices must be followed to assure durability and trouble-free performance. Areas for economy in basic design and house construction are covered in numerous publications. However, skimping on materials or using poor building practices in constructing the house frame saves little. Such practices may reduce the strength and rigidity of the structure and cause difficulty in attachment of cladding materials and trim. Therefore, the details in this document are not intended to be bare minimums; rather, they reflect requirements for producing sound, low maintenance wood frame buildings.

The first approach to achieving a strong, durable structure, involving economical use of materials, is to follow a basic modular plan for layout and attachment of framing members. Such methods use a 4-foot design module, which governs a 16-inch spacing of joists, studs, rafters and panel sheathing products. This module also provides for alternate 24-inch spacing of floor, wall and roof framing where floor and roof trusses are used, and accommodates 24-inch spacing of studs where wind loads permit, or where larger studs are required for thicker insulation or heavier floor and roof loads.