236 Section 2 Foundations and Framing firestopping needed is built into the floor frame at the second floor level. It prevents the spread of fire in a horizontal direction. It also serves as solid bridging, holding the joists in a plumb (vertical) position. Referring to the illustrations in Figure 10-3A, note that a carpenter usually places a strip of insu- lation, called a sill sealer, between the sill plate and the foundation. This prevents heat from being lost at that point. Architectural plans specify the type of fram- ing. There will be section views of floors, walls, and ceilings. A typical detail drawing of first floor framing includes not only the type of construction, but also the size and spacing of the various mem- bers. See Figure 10-4. Chapter 5 of the International Residential Code (IRC) covers floor framing. 10.1.2 Balloon Framing In balloon framing, the studs are continu- ous from the sill to the rafter plate. A ribbon let into the studs supports the second floor joists. They are spiked to the stud as well, Figure 10-5. Firestopping must be added to the space between the studs. This stud space, which also occurs in load-bearing partitions, permits easy installa- tion of mechanical system components, such as plumbing, wiring, and air ducts. In balloon framing, shrinkage is reduced because the amount of cross-sectional lumber is low. Wood shrinks across its width, but practi- cally no shrinkage occurs lengthwise. Thus, the high vertical stability of the balloon frame makes it adaptable to two-story structures, especially where masonry veneer or stucco is used on the outside wall. Though once popular, this type of framing is rarely, if ever, used today. Balloon framing requires longer studs and the addition of firestopping at each floor level, and it does not pro- vide the platform (floor) on which to assemble the wall framing. However, many balloon frames still exist and carpenters may encounter this design in remodeling or repair projects on older buildings. 2 x 4 Stud – 16" O.C. 2 x 4 Sole plate 5/8" Ext plywood 3/4" Composition sheathing 2 x 10 Joist – 16" O.C. 2 x 10 Header 5/8" Anchor bolts – 6'-0" O.C. 2 x 6 Sill Sill sealer Foundation wall 8" reinforced concrete A B C 3/4" Composition sheathing 2 x 4 Stud – 16" O.C. 2 x 4 Sole plate 5/8" Ext plywood 2 x 10 Header 2 x 10 Joist – 16" O.C. 5/8" Anchor bolts – 6'-0" O.C. 2 x 6 Sill Sill sealer Foundation wall 8" reinforced concrete Roman face brick common bond 2 x 6 Sill Sill sealer Foundation wall 12" reinforced concrete 2 x 6 Stud – 24" O.C. 3/4" Composition sheathing 2 x 6 Sole plate 5/8" Ext plywood 2 x 10 Joist – 16" O.C. 2 x 10 Header 5/8" Anchor bolts – 6'-0" O.C. Goodheart-Willcox Publisher Figure 10-4. Architectural detail drawings show methods of construction as well as the materials to use. A—Sheathing brought to the foundation. B—Sheathing brought to the sole plate. C—Brick veneer construction. Copyright Goodheart-Willcox Co., Inc.