Power Point Presentation Publisher The GoodheartWillcox Co Inc
Power. Point Presentation Publisher The Goodheart-Willcox Co. , Inc. Tinley Park, Illinois © Goodheart-Willcox Co. , Inc. 1 Permission granted to reproduce for educational use only
Chapter 13 Sill and Floor Construction 2 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Chapter 13 Overview • • Introduction Platform Framing Balloon Framing Joists and Beams Floor Trusses Subfloor Cantilevered Joists 3 © Goodheart-Willcox Co. , Inc. (continued) Permission granted to reproduce for educational use only
Chapter 13 Overview • Framing Under Slate or Tile • Engineered Wood Products • Post and Beam Construction 4 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Learning Objectives • Explain the difference between platform and balloon framing. • Plan the appropriate floor support using joists or trusses for a structure. • Determine proper joist sizes using a typical span data chart. • Describe the components of a floor system. 5 © Goodheart-Willcox Co. , Inc. (continued) Permission granted to reproduce for educational use only
Learning Objectives • Explain the principles of post and beam construction. • Select the appropriate engineered wood products for specific applications in residential construction. 6 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Introduction • Framing methods vary from one section of the country to another. • Personal preference and experience are also factors. • Two basic types of floor framing are: – Platform framing. – Balloon framing. 7 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Introduction • Typical floor framing structural components include: – Plates. – Joists. – Studs. • Post and beam construction is also used for walls and floors. 8 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Platform Framing • In platform framing, floor joists form a platform on which the walls rest. • Another platform rests on top of the walls when there is a second story. • Platform framing is used more extensively than balloon framing. • The platform automatically provides a fire-stop between floors. 9 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Platform Framing • Construction is safe because work is performed on a solid surface. • The sill is the starting point in constructing a floor. – Rests on the foundation and supports the floor joists or the studs. – Generally 2" x 6" lumber. – Box sill construction is generally used, which consists of a 2" x 6" plate called a mudsill. 10 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Platform Framing • Box sill construction. 11 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Platform Framing • Detail of the first and second floor. • Using box sill construction. 12 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Sealing the Sill • A seal is required between the foundation and sill plate. • The seal prevents outside air from entering the house. 13 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Balloon Framing • Balloon framing has diminished in importance in recent years. • Distinguishing features include: – Wall studs rest directly on the sill plate. – Each floor “hangs” from the studs. • Two advantages of balloon framing are: – Small potential shrinkage. – Good vertical stability. 14 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Balloon Framing • Disadvantages of balloon framing are: – Less than desirable surface on which to work during construction. – The need to add fire-stops. • Two types of sill construction are used: – Solid (standard). – T-sill. 15 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Balloon Framing Sill Construction • Solid (standard) sill. • Studs are nailed directly to the sill and joists. • No header is used. 16 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Balloon Framing Sill Construction • T-sill construction. • Header rests on the sill and serves as a fire-stop. • Studs rests on the sill and are nailed to the header as well as the 8" or 10" wide sill plate. 17 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Balloon Framing for Second Floor • Joists are supported by a ribbon and nailed to the studs on the second floor level. 18 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Joists and Beams • Joists provide support for the floor. • Usually made from a common softwood. – Southern yellow pine, fir, larch, hemlock, or spruce. • Engineered wood and metal joists are also available. • Floor joists range in size from 2" x 6" to 2" x 12". 19 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Joists and Beams • Standard lumber sizes. (National Forest Products Association) © Goodheart-Willcox Co. , Inc. 20 Permission granted to reproduce for educational use only
Joists and Beams (Joists) • Size of joist required depends on the span, load, species and grade of wood, and joist spacing. • When using metal joists, the gauge of metal should be considered instead of species and grade of lumber. • Floor joists may be spaced 12", 16", or 24" on center. 21 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Procedure for Using Span Data Chart • • Select species of wood to be used. Select appropriate live load. Determine lumber grade to be used. Scan the lumber grade row and note the maximum spans. • Select the joist size and spacing that will support the desired live load; 16" OC spacing is typical. 22 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Floor Joist Span Data 23 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Floor Joist Span Data 24 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Floor Joist Span Data 25 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Span Data Example • Span is 14'-0" and number one dense southern pine is to be used. • Live load is 30 pounds per square foot. • Chart shows the following choices. – 2" x 8" joists 12" OC or 16" OC. – 2" x 10" joists 12" OC, 16" OC, or 24" OC. – 2" x 12" joists 12" OC, 16" OC, or 24" OC. • Best selection is 2" x 8" joists, 16" OC. This will span up to 14'-5". 26 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Steel Floor Joists • Steel floor joists are beginning to be accepted for residential construction. • Joist depths ranging from 6" to 12" with thicknesses from 0. 034" to 0. 101" are generally used. • Usual spacing is 24" OC, but other spacing is also used. 27 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Steel Framing Detail • Typical steel framing where floor joists bear on the foundation. 28 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Joists and Beams (Beams) • When the span is too great for unsupported joists, a beam or loadbearing wall is needed to reduce the span. • A beam may be a solid timber, built-up beam, or a metal S- or W-beam. • Load-bearing walls may be concrete block, cast concrete, or frame construction. 29 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Methods of Supporting Floor Joists with Beams 30 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Supporting Partition Walls • Partition walls that run parallel to the floor joists require added support. 31 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Openings in the Floor • Openings in the floor for stairs and chimneys required double joist framing. 32 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Cross Bridging • Cross bridging is used to stiffen the floor and spread the load over a broader area. • Bridging boards or metal bridging are used. 33 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Metal Bridging 34 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Floor Trusses • A truss is a rigid framework designed to support a load over a span. • Floor trusses are often used in place of floor joists in residential construction. • Floor trusses consist of a top chord, bottom chord, and web. • Chords are the horizontal flanges on the top and bottom of the truss. • The web is the truss framework. 35 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Floor Trusses • Trusses provide clear spans with a minimum depth in a lightweight assembly. (Trus Joist) © Goodheart-Willcox Co. , Inc. 36 Permission granted to reproduce for educational use only
Engineered Floor Trusses • Engineered floor trusses are designed with the aid of computers. • Usually fabricated from 2" x 4" or 2" x 6" lumber and generally spaced 24" OC. • Each truss has a built-in camber. • Stress-graded lumber is used in their construction to reduce material. • Webs may be metal or wood. 37 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Typical Truss Webs (Trus. Wal Systems, Inc. ) © Goodheart-Willcox Co. , Inc. 38 Permission granted to reproduce for educational use only
Subfloor • The subfloor is attached to the top of the floor joists and provides a work surface during construction. • Plywood, tongue-and-groove boards, common boards, and other panel products are used for subfloors. – Panel products reduce installation time. – 5/8" or 1/2" thick plywood is preferred. 39 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Typical Panel Products (Georgia-Pacific Corporation) © Goodheart-Willcox Co. , Inc. 40 Permission granted to reproduce for educational use only
Installing Subfloor Panels • Joist spacing must be very accurate. • All panel edges must be supported. 41 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Installing Subfloor Panels • Plywood grain direction of the outer plies should be at right angles to joists. • Panel products should be staggered so that end joints of adjacent panels are on different joists. • Panels may be glued as well as nailed to the joists to increase strength and reduce squeaking and nail pops. 42 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Cantilevered Joists • Cantilevered joists are required when a section of the floor projects beyond a lower level. • When floor joists run perpendicular to the cantilevered section, longer joists form the cantilever. • When joists are parallel to the overhanging area, cantilevered joists are required. 43 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Cantilevered Joists • Generally, joists should extend inside the structure twice the distance they overhang. 44 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Framing Under Slate or Tile • Flooring materials such as ceramic tile, slate, or stone floors require a substantial base. • If a concrete base is provided, the floor framing must be lowered to provide for the concrete. • Dead weight may be as much as 50 pounds per square foot. 45 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Framing Under Slate or Tile • A smaller size joist may be used and the space between joists reduced to provide adequate support. • Cement mortar mix is generally used for the base. 46 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Engineered Wood Products • Engineered wood products (EWPs) combine wood veneers and fibers with adhesives to form beams, headers, joists, and panels. • EWPs have uniformly high quality and strength. • They increase the supply of usable wood from smaller and inferior trees. 47 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Engineered Wood Products • The use of engineered wood products will continue to grow. • Advances in adhesive technology have made EWPs possible. – Phenol-formaldehyde and ureaformaldehyde are the most common types. – Phenolics are more expensive than urea resins. 48 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Engineered Wood Products • Band boards are available in 9 -1/4", 11 -1/4", 12", 14", and 16" depths. • Engineered headers are available in 1 -1/4" depth and 3 -1/2" width. (Alpine Structures) © Goodheart-Willcox Co. , Inc. 49 Permission granted to reproduce for educational use only
Engineered Wood Products • Advantages of EWPs: – High quality and consistency. – No knots, checks, or warps. – Uniformly dried to 8% to 12% moisture content. – Provides superior design flexibility. • Disadvantage of EWPs: – Lack of industry standards. 50 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Engineered Wood Products • Application of EWPs. 51 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Oriented Strand Board • Oriented strand board (OSB) is made from long strands of wood and resin. • First introduced in 1978 as a low-quality particle board panel. • Aspen is the preferred wood for making OSB. • Outer layers are oriented to the long dimension, others are perpendicular. 52 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Oriented Strand Board The Engineered Wood Association) © Goodheart-Willcox Co. , Inc. 53 Permission granted to reproduce for educational use only
Oriented Strand Board • Advantages of OSB: – Less expensive than plywood. – Unique appearance can be appealing as a design element. • Disadvantages of OSB: – Subject to swelling. – Not designed for exposure to the elements. 54 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Oriented Strand Board • OSB is made in panel sizes similar to plywood, typically 4' x 8'. • Available in sizes up to 8' x 24'. • Allow 1/8" space along edges to prevent buckling problems. • Use the same nailing schedules that apply to plywood. 55 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Parallel Strand Lumber • Parallel strand lumber (PSL) is made from thin strands of wood. • Fairly new category of EWP. • Used for beams, columns, and headers. • High strength and span capacity. • Low-moisture content eliminates shrinking and checking. • Large billets 12" wide by 17" deep are formed and then sawn to specific sizes. 56 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Parallel Strand Lumber (Alpine Structures) © Goodheart-Willcox Co. , Inc. 57 Permission granted to reproduce for educational use only
Parallel Strand Lumber • Advantages of PSL: – Very strong. – Allows long spans and more design flexibility. • Disadvantages of PSL: – Engineered connections are required for side-loading joists on one side. – Should not be drilled or notched. – Storage conditions should prevent swelling. 58 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Parallel Strand Lumber • Widths available from 1 -3/4" to 7". • Two plies of 2 -11/16" members will match a typical 5 -1/2" wall. • Lengths up to 66' available. • Eliminates the need for built-up beams. (Alpine Structures) © Goodheart-Willcox Co. , Inc. 59 Permission granted to reproduce for educational use only
Laminated Veneer Lumber • Laminated veneer lumber (LVL) is made from veneers stacked parallel to each other. • LVL is used for headers, beams, joists, columns, and flanges for wood I-beams. • Similar to plywood, but all plies are parallel to provide maximum strength. • Southern yellow pine and Douglas fir are generally the woods of choice. 60 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Laminated Veneer Lumber • LVL is produced in a continuous billet up to 1 -3/4" thick and 4' wide and two or more billets can be glued together to form thicker pieces. (Trus Joist) © Goodheart-Willcox Co. , Inc. 61 Permission granted to reproduce for educational use only
Laminated Veneer Lumber • Advantages of LVL: – High strength allows long spans. – Can be built-up on site to form larger members. • Disadvantages of LVL: – More expensive than solid lumber. – Lower moisture content than solid lumber. – Must be sized for specific load conditions. 62 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Laminated Veneer Lumber • The 1 -3/4" thick billet is most common. • Can be used individually for joists or combined to form headers or beams. • Available in depths from 5 -1/2" to 14" and lengths up to 66'. • LVL generally should not be mixed with solid lumber in the same floor assembly. • LVL beams should not be drilled. 63 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Glue-Laminated Lumber • Glue-laminated members (glulam beams) consist of 1 x or 2 x lumber glued into desired shapes. • Glue-laminated beams, columns, and arches were the first engineered wood products. • Virtually any length or depth can be produced. 64 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Glue-Laminated Lumber • This construction makes extensive use of glue-laminated beams. 65 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Glue-Laminated Lumber • Glue-laminated beams are accepted by all three US model building codes. • Three appearance grades are available. – Industrial grade: The least attractive containing visible glue stains, press marks, and knot holes. – Architectural grade: Sanded on four sides with knot holes filled with putty. – Premium grade: All checks and holes filled. 66 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Glue-Laminated Lumber • Advantages of glulams: – High strength. – Available either straight or cambered. – Dimensionally stable and attractive. • Disadvantages of glulams: – Cost is high. – Requires special handling and storage. – Requires special equipment to handle. 67 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Glue-Laminated Lumber • Installation – Technical support is generally required. – Producers provide span charts, installation details, technical assistance. – Special connectors are required for these large members and heavy loads. – Special handling is required to reduce checking and preserve the finish. 68 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Wood I-Beams or Joists • Wood I-beams or joists are generally made from 2" x 4" machined-stressed lumber or LVL. • Webs are usually made from 3/8" OSB. • They are available in flange widths of 1 -3/4" and 2 -5/16" and depths from 9 -1/2" to 20" and lengths up to 66'. • Presently, each manufacturer uses their own proprietary process. 69 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Wood I-Beams or Joists (Boise Cascade Corporation) © Goodheart-Willcox Co. , Inc. 70 Permission granted to reproduce for educational use only
Wood I-Beams or Joists • Advantages of wood I-beams: – Speed of construction. – Have knockout holes for plumbing and electrical cable. – Dimensionally stable and very straight. • Disadvantages of wood I-beams: – Require more effort to cut. – Not universally accepted. – More expensive than lumber or trusses. 71 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Wood I-Beams or Joists • Installation of wood I-beams are similar to traditional floor joists or rafters. – Typical nails, tools, and metal connectors can be used. – Should not be mixed with solid lumber in the same assembly. – Web stiffeners or blocks are normally used at bearing points. 72 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Wood I-Beams or Joists • Several types of engineered lumber are used in this dwelling. (Boise Cascade Corporation) © Goodheart-Willcox Co. , Inc. 73 Permission granted to reproduce for educational use only
Post and Beam Construction • Post and beam construction provides greater freedom of design. • The system uses larger structural sizes, framing connectors, and unique joining methods. • Posts carry most of the weight • The walls are usually curtain walls. • Curtain walls provide for wide expanses of glass without the need for headers. 74 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction 75 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction (The Engineered Wood Association) © Goodheart-Willcox Co. , Inc. 76 Permission granted to reproduce for educational use only
Post and Beam Construction • Curtain wall example. (Pozzi Wood Windows) © Goodheart-Willcox Co. , Inc. 77 Permission granted to reproduce for educational use only
Post and Beam Construction • Foundation for a post and beam structure may be continuous or isolated footings on which each post is located. • Posts should be at least 4" x 4" or 6" x 6" if they support the floor. • Beams should be solid, laminated, reinforced with steel, or plywood box beams. 78 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction • A variety of beams used in post and beam construction. 79 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction • The spacing and span of the beams will be determined by the size and type of materials and the load to be supported. • Generally, a span of 7'-0" may be used when 2" thick tongue-and-groove decking is applied. • Thicker beams should be used if the span exceeds 7'-0". • Span tables are provided in the text. 80 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction • There are two systems of roof beam placement: – Longitudinal method: Beams are placed at right angles to the roof slope; roof decking is laid from the ridge to the eaves. – Transverse method: Beams follow the roof slope; decking runs parallel to the roof ridge. 81 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction • The longitudinal method. 82 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction • The transverse method. 83 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction • Metal connectors. 84 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction • Installation – Nailing does not provide a satisfactory connection in post and beam construction; lag bolts are used. – Metal plates or connectors are used to attach post and beam segments. – Decking planks range in thickness from 2" to 4" and are usually tongue-and-grooved along the long edges. 85 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
Post and Beam Construction • Several plank designs used in post and beam construction. 86 © Goodheart-Willcox Co. , Inc. Permission granted to reproduce for educational use only
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