234 Section 2 Foundations and Framing or repair older homes should know about it. This type of framing is discussed in Chapter 28, Remodeling, Renovating, and Repairing. • Post-and-beam framing, also called plank-and- beam framing, is different from the other two types. Its heavy structural members are at least 4″ thick. This kind of construction is covered in Chapter 25, Post-and-Beam Construction. In both platform and balloon framing, the com- mon structural members are joists, studs, plates, and rafters. Material with a nominal 2″ thick- ness is used. While sawn 2″ lumber is still used extensively for framing, engineered lumber often replaces sawn materials. These new materials include I-joists, open-web truss joists, laminated- veneer lumber, and laminated-strand lumber. They are lightweight, have consistent strength, can be purchased in long lengths, and use fewer natu- ral resources than sawn lumber. 10.1.1 Platform Framing In platform framing, the first floor is built on top of the foundation wall as a platform. It provides a work area for safely and accurately assembling and raising wall sections. Wall sections are one story high. Outside walls and interior partitions support rafters or upper stories. Each floor is separately framed. Platform framing is satisfactory for both one-story and multistory structures. Settlement due to lumber shrinkage occurs in an even and uniform manner throughout the structure. Figure 10-2 shows the first-floor platform of a platform frame. Usually, the first-floor platform Temporary brace Stud Top plate Corner bracing (use 1 x 4 let-in bracing, steel X-strapping, rigid steel braces, or structural sheathing such as plywood, flakeboard, or oriented strand board.) Sole plate Plywood subfloor Stringer joist Anchored sill plate Foundation wall Header joist Windowsill Window header Goodheart-Willcox Publisher Figure 10-1. In platform framing, a frame of joists provides support for the walls of the first level of the building. Ceiling joists or floor joists for the second level rest on the top plate. Copyright Goodheart-Willcox Co., Inc.