262 Section 2 Foundations and Framing 21. If the joist spacing is 24″ O.C. and there are no floor openings, how many joists are needed? 22. What is the total length of header or rim joist needed for the floor frame? 23. How many sheets of 4′ × 8′ sheathing are needed for the subfloor? (Assume no floor openings and no extra sheathing for waste.) Extending Your Knowledge 1. Obtain a set of architectural plans for a house with a conventional basement. Study the methods of construction specified in the section and detailed drawings. Then, prepare a first-floor framing plan. Start by tracing the foundation walls and supports shown in the basement or foundation plan and then add all joists, headers, and other framing members. Your drawing should be similar to the partial drawing shown in Figure 10-31. 2. Research the advantages and disadvantages of using different types of floor joists for residential construction. Compare solid dimension lumber joists, open-web trusses, and I-joists. Consider ease of installation, material cost, strength-for-size, and other factors such as ease of installing plumbing and heating lines. Academic and STEM Activities 1. Mathematics. Working from a set of architectural plans for a single-story house, develop a list of materials required to frame the floor. Select the type of subflooring (if not specified) and estimate the amount of material needed. Check material prices at several local sources, such as home improvement centers or lumberyards, and prepare a cost estimate. If the prices significantly differ among the sources, prepare a high estimate and a low estimate. 2. Language Arts. From the local building code in your area, find the requirements for floor framing. Prepare a list of the requirements along with sketches to clarify complicated written descriptions. Make an oral report to your class and pass around your sketches. Communicating about Carpentry 1. Speaking and Listening. Divide into groups of four or five students. Using your textbook as a starting point, research your topic and prepare a report on how to install platform floor framing. As a group, deliver your presentation to the rest of the class. Take notes while other students give their reports. Ask questions about any details that you would like clarified. 2. Speaking. Pick a figure in this chapter. Working with a partner, tell and retell the important information being conveyed by that figure. Through your collaboration, develop what you and your partner believe is the most interesting verbal description of the importance of the chosen figure. Present your narration to the class. 3. Speaking. Obtain (or draw) a floor framing assembly. Label the areas on the assembly where these types of components are located: joists, sills, anchor straps, anchor bolts, joists, openings in the framing, and bridging. Be prepared to explain the purpose of each component. Copyright Goodheart-Willcox Co., Inc. Chapter 10 Floor Framing 261 Summary There are three basic types of framing used in residential construction: platform (western) framing, balloon framing, and post-and-beam framing. Platform framing is by far the most com- mon. Balloon framing is no longer used for new construction. In platform framing, the first floor is constructed on top of the foundation wall and used as a work area for constructing the remain- ing wall, floor, and roof framing components. Floor framing consists of joists that rest on the foundation walls or girders. The joist ends rest on a sill that is fastened to the foundation wall and are held in position by a joist header fastened around the perimeter. Bridging may be installed between joists to hold joists vertical and help transfer loads from one joist to the next. Special framing must be used for floor areas cantilevered beyond the foundation walls. Some building plans call for open-web trusses for floor joists. They are light, strong, and provide space for electrical, piping, and HVAC installations. Subfloors of OSB or ply- wood are installed on top of the joists, making the whole floor structure more rigid. Proper fasten- ing of the subfloor to the joists is important for strength, smoothness, and durability. Review Questions Answer the following questions using the information in this chapter. 1. The type of framing used in most residential construction is ______ framing. 2. The studs of a balloon-type frame run continuously from the ______ to the rafter plate. 3. ______ may be solid timbers, built-up lumber, engineered lumber, or steel beams. 4. The sill may be ______ with the outside of the foundation or it may be set back to allow for the thickness of the sheathing. 5. In residential construction, the deflection of first floor joists under normal live loads should not exceed ______ of the span. 6. Joists must be ______ around openings in the floor for stairways. 7. A member of the floor frame that runs from the band joist to a header of an opening is called a(n) ______ joist. 8. True or False? Regular bridging is designed to keep joists in vertical position and transfer the load from one joist to the next. 9. True or False? Steel bridging is installed with nails and a nail gun. 10. For cantilevered floor framing, if the run of joists is parallel to the supporting wall, extend the ______ joists inward two to three times the length of the overhang. 11. Most I-joists have perforated ______ that can be removed to provide holes for pipes and wiring. 12. Most trusses are fabricated with wooden ______ connected by galvanized steel ______. 13. True or False? The IRC states that anchor bolts may not be placed in less than 7″ of concrete. 14. Explain the purpose of subflooring and underlayment. 15. Identify five major components needed to lay out and construct a floor assembly. 16. ______ bridging is easier to cut and install when there are odd-sized spaces in a run of regular cross bridging. 17. Explain the purpose of herringbone bridging. 18. True or False? OSB should be installed with the long edges running perpendicular to the joists. 19. Describe how to perform an estimate for materials. For Questions 20–23, use the following simplified sketch of a floor frame outline to answer the questions. 20. If the joist spacing is 16″ O.C. and there are no floor openings, how many joists are needed? Joists run in this direction 24'– 0" 36'– 0" Copyright Goodheart-Willcox Co., Inc. Construction Careers Chapter 11 Wall and Ceiling Framing 293 Lakeview Images/Shutterstockmateri-aofinmeasuring Framing carpenters work mostly with structural als made of wood. They work on all sections build- ing, from top to bottom. They are trained the use of hand tools and power tools, as well as devices. Most of the carpenters employed in residen- tial and light commercial construction are fram- ing carpenters. They are sometimes referred to as rough carpenters to distinguish them from the finish carpenters who do trim and specialty work. Framing carpenters primarily work with wood as a structural material. They fabricate the floor structures, wall sections, and roof framing of the building. In recent years, framing carpenters have become increasingly involved with the cutting, fit- ting, and fastening of light steel structural mem- bers (joists studs), especially in commercial construction.and Approximately 1/3 of all carpenters are self- employed. Another 1/3 work for general contractors. The remaining 1/3 are spread among specialty con- tractors, manufacturing firms, government agencies, and other employers. The growth of manufactured housing has created jobs for framing carpenters in firms that prefabricate building sections or entire structures. Basic skills for framing carpenters are the abil- ity to make use of measuring devices and to read and accurately follow construction drawings. They must be able to efficiently and safely use a variety of hand and power tools. Framing carpentry is strenu- ous work, involving lifting and carrying, standing or kneeling for long periods, and working in situations where the danger of injury from falls or other acci- dents is present. Most of the work is done outdoors, often in rainy, dusty, cold, or hot weather conditions. Wearing appropriate clothing and proper personal protective gear is important. Framing carpenters acquire their skills in a vari- ety of ways. Many learn through informal on-the-job training working with more experienced carpen- ters. Others enter the field from vocational school programs or take part in formal apprenticeship training. A carpentry apprenticeship typically is 3–4 years in length and combines classroom training with practical experience and instruction on the jobsite. Because they are exposed to most aspects of the construction process, carpen- ters who work for general contracting firms have opportunities for advancement to positions such as foreman, carpentry supervisor, or general con- struction supervisor. Framing Carpenter Copyright Goodheart-Willcox Co., Inc. Designed to reinforce the material covered in the chapter. Review Questions Provides an additional review tool for the student. Summary Brief profiles of job specialties found in the construction field. Provides exposure to different career opportunities. Construction Careers Various tasks and projects designed to help the student expand their knowledge of the chapter content or gain competence in the subject area. Extending Your Knowledge Activities designed to relate the book’s content to other curriculum, such as language, mathematics, science, and social studies. Academic and STEM Activities Activities designed to improve and develop language skills, such as reading, speaking, and listening. Communicating about Carpentry Copyright Goodheart-Willcox Co., Inc. ix