ACH 121 Lecture 07 (Wood) Part 2
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The document discusses various aspects of wood construction including lumber grades, structural members, panels, nails, and fasteners. It describes how lumber is graded based on strength, stiffness, and appearance. It also outlines different types of structural wood members like beams, joists, and engineered wood composites. Additionally, it covers wood panel standards and varieties of panels including plywood, OSB, and fiberboard. Finally, it discusses common wood fasteners such as nails, screws, bolts, and toothed plates.
![Lumber Pricing Unit BOARD FEET One board foot = 1 inch X 12 inch X 1 foot Calculation based upon Nominal dimensions # of board feet = [(thickness” X width”) / 12] X length’ Example; 2x8 that is 10 feet long [(2x8)/12] X 10 = 13.33 board feet (bf) Lumber Pricing Factors Species Grade (and drying process) Lumber size](https://image.slidesharecdn.com/ach121-lecture07woodpart2-090923101609-phpapp02/85/ACH-121-Lecture-07-Wood-Part-2-10-320.jpg)
ACH 121 Lecture 07 (Wood) Part 2
- 1. WOOD CONSTRUCTION Lumber Grades Structural Members & Panels Nails & Fasteners Part 2 Professor Brandi R. Shepard© ACH 121-Materials and Methods 1
- 2. LUMBER GRADES Graded by: Strength & Stiffness (Structural Lumber), or Appearance (Finish Lumber) Lumber sold by - Species and Grade Better Grade Higher price Scarce or Higher Quality Species Higher price Strength is based on lumber species and lumber grade
- 3. LUMBER GRADES Classified by Use , Manufacture & Size USE Classification Yard lumber Consists of grades, sizes & patterns generally used for construction & building purposes Structural lumber Lumber is 2” or more in nominal thickness Factory & shop lumber Windows, doors, millwork
- 4. LUMBER GRADES MANUFACTURE Classification Rough lumber Not dressed (surfaced) Sawed, edged & trimmed Dressed lumber Surfaced lumber to make it smooth S1S-surfaced on one side S2S-surfaced on two sides S1E-surfaced on one edge S2E-surfaced on two edges S4S-surfaced on both sides & edges S4S
- 5. LUMBER GRADES MANUFACTURE Classification Worked lumber Matched lumber (tongue & groove) Shiplapped lumber (rabbetted on both edges) Patterned lumber (shaped to pattern or molded form)
- 6. LUMBER GRADES SIZE classification Nominal size Boards Less than 2 inches thick & more than 2 inches wide Sheathing, subflooring, trim, siding & paneling Dimension lumber Structural elements Timbers More than 5” in dimension Beams, posts & sills
- 7. Lumber Thickness and Width NOMINAL Thickness < 2 inches - Boards 2 to 4 in. - Dimension Lumber = to or > 5 inches - Timbers Widths Framing Lumber - 2, 4, 6, 8, 10, 12 inches Finish /lumber - 1 inch (typ.)
- 8. Lumber Thickness and Width ACTUAL Nominal not equal to Actual dimensions Lumber SAWN Close to Nominal Then dried and surfaced Up to 6 inches - actual is 1/2 inch less Greater than 6 inches - actual is 3/4 inch less
- 9. Lumber Lengths Typically; Two (2) foot increments Sizes; 8’, 10’, 12’, 14’, & 16’ (longer available) Exceptions; 93 inch studs Special order lengths
- 10. Lumber Pricing Unit BOARD FEET One board foot = 1 inch X 12 inch X 1 foot Calculation based upon Nominal dimensions # of board feet = [(thickness” X width”) / 12] X length’ Example; 2x8 that is 10 feet long [(2x8)/12] X 10 = 13.33 board feet (bf) Lumber Pricing Factors Species Grade (and drying process) Lumber size
- 11. Panel Standards & Grading Established by American Plywood Association (APA) Standards based on; Structural adequacy Dimensional Stability Durability of Adhesive Grade Stamp for OSB Panel
- 12. STRUCTURAL MEMBERS & PANELS Wood Beams Solid timber (one large piece of wood) Milled Framing Lumber
- 13. STRUCTURAL MEMBERS & PANELS Wood Beams Built-up: (multiple framing members) Milled Framing Lumber
- 14. STRUCTURAL MEMBERS & PANELS Wood Beams Glue Laminated: (horizontal thick layers of wood) Engineered Lumber
- 15. STRUCTURAL MEMBERS & PANELS Wood Beams Laminated Veneer Lumber “LVL”: (vertical thin layers of wood) Engineered Lumber
- 16. STRUCTURAL MEMBERS & PANELS Wood Beams Parallel Strand Lumber “PSL”: (strips of wood) Engineered Lumber
- 17. STRUCTURAL MEMBERS & PANELS Wood Beams Plywood Box Beam: (hollow shell) Engineered Lumber
- 18. STRUCTURAL MEMBERS & PANELS Wood Joists Butt (framing) Scarf (trim) Finger Joint (milling)
- 19. Laminated Wood ( Glulam ) Lamination Process SELECT LUMBER, GRADE JOINTS - FINGER OR SCARF ADHESIVES BASED ON EXPECTED MOISTURE Why Laminate? Create a size not available naturally Create Shapes Improve Quality
- 21. Laminated Wood
- 23. Wood Manufactured Components Trusses Wood I-Joists Beams Panel Components Also known as Engineered Lumber
- 24. New Age of Building Materials Becoming Common Place in Homes by Jill Mayfield, City of Austin Green Building Program There's a new breed of building products that are changing the face of the building industry. They're called engineered building materials, and as conventional building materials become more expensive and harder to get, more homebuilders are using these new materials. One class of these products that is becoming widely used is "engineered" wood. Wood that once laid on the mill floor and was thrown away is now part of a new age of building materials. But are engineered wood products weaker or inferior to solid pieces of lumber? No, they are designed by licensed structural engineers to do their job well, and have withstood rigorous testing at national labs. The advantages of engineered wood are better performance for the cost, a reduced use of natural resources, and less waste on the job site. One of the most common uses of engineered wood are roof and floor trusses . The builder gives the house plans to a licensed engineer at the truss mill who designs a configuration of wood members and special metal fasteners that safely bear the load of the building. A major environmental benefit is that short pieces of small dimension lumber can be used in a truss. This spares the trees in old growth forests-the source of the longest spans of lumber. Engineered studs are another wood product gaining acceptance among builders and homeowners. These studs are made of short pieces of wood that have finger-like joints cut in each end that are glued together end to end. Wood that was once considered too short to be used for structural purposes, and often just went to the landfill, is now made into finger-jointed studs. Engineered studs are strong, straight and less likely to warp after installation like many solid lumber studs. If your builder, architect, or designer is specifying engineered products in your home, it means he or she is using smart and proven building technology that is cost-effective. And by incorporating engineered materials into your home, the builder is using a material that may have once gone to waste, and is protecting resources-such as old growth forests-that can never be replaced. http://www.greenbuilder.com/general/articles/AAS.newagebldg.html
- 25. Wood Manufactured Components TRUSSES Types of Trusses - Floor & Roof Floor Trusses Roof Trusses
- 27. Where and How Built? Most factory built (pre-engineered) Most 2X4 or 2X6 w/ toothed fasteners Order how? Span Loads Pitch (roof) Overhang Wood Manufactured Components TRUSSES
- 28. Wood Manufactured Components I-JOIST Uses Floors and Roofs Sizes Typically, 9-1/2” TO 24 “ DEEP Length up to 40 FEET+ Composition TOP & BOTTOM - LUMBER OR Laminated WEB - OSB, PLYWOOD Cost Comparable to a 2x
- 29. Why Use Trusses or I-Joists? Less material (less weight) More efficient use of wood Increased Span Increased dimensional stability Installation savings (labor)
- 30. Structural Composite Lumber (LVL)
- 32. STRUCTURAL MEMBERS & PANELS Wood Panels Plywood (alternating veneers of lumber) Wood Panels Process: Rotary Slicing
- 33. Wood Panel Products Why Panelize? More “controlled” product Efficient use of forest products Increase labor productivity Types Plywood panels Composite panels Nonveneered panels
- 34. Veneered Panels - Plywood Thin layers of veneer glued together Odd number of veneers Alternating direction of veneers Face veneers parallel Size: 4’x8’ panels Thickness: ¼” to 1”
- 35. Composite Panels Parallel outside face veneers Core - Reconstituted wood fibers
- 36. Veneer Grades Based on the smoothness & integrity of the veneers Classifications; A, B, C (plugged), C, D Price Variances C Grade C Plugged A Grade
- 37. Non-veneered Panels Oriented Strand Board (OSB) Strips are oriented for more strength Waferboard “ flakes”; un-oriented Particleboard Medium Density Fiberboard (MDF) Particleboard Fiberboard
- 38. Oriented Strand Board (OSB) Long strand like wood particles Alternate grain orientation (3-5 layers) Compressed / glued Strongest of the Non-veneered Uses; Sheathing for floor, roofs, & siding
- 39. Plywood vs. OSB 1994 American Plywood Association (APA) changes name to “APA - Engineered Wood Products” 1994-1995 (per Georgia Pacific) Plywood Production 19 billion sf and declining OSB Production 10 billion sf and increasing 1999 - OSB market share > Plywood
- 40. Waferboard & Particleboard Waferboard Large wafer-like particles - No orientation Uses; Low moisture areas Particleboard Small wood particles No orientation Uses; Low moisture areas
- 41. Chemical Treatment Combustibility Fire retartant Impregnated under pressure Decay & Insect Pressure impregnated Up to a 30 year life Types CREOSOTE PENTACHOROPHENOL (oily, can’t paint) WATERBORNE SALTS (greenish, can paint) Chromated Copper Arsenate (CCA) being phased out
- 42. Wood Polymer Composite Planks Advantages: Decay Resistance Easy Workability
- 43. Wood Fasteners Nails Wood & Lag Screws Bolts Toothed Plates Sheet Metal & Metal Framing Devices Machine Driven Staples & Nails Adhesives
- 44. Nails Sharpened metal pins Installation: Hammer or mechanical nail gun Common Nails Finish Nails Other types
- 45. NAILS & FASTENERS Basic Types: Common (typical nail) Finish (smaller head) Ring (edges to grip) Cement (glue-coated) Finishes: Steel (will rust) Stainless steel (won’t rust) Aluminum (won’t rust) Not structural (used for siding & trim) Galvanized (rust-resistant)
- 46. 16d Galvanized 16d Sinker Deformed Shank 10d Galv. Spiral Finish Nail Roofing Nail (far right)
- 47. Nails Size - Measured in pennies Coatings Bright/ Plain uncoated steel Corrosion-resistant Resin/Vinyl Why is it measured in pennies?
- 49. Anchorage End Nail parallel to grain weakest Basic Nailing Methods: Face Nail 90° to grain strongest Toe Nail diagonal with grain “ OK” method
- 50. Machine Driven Nails & Staples Nail Guns, Staple guns Pneumatic (or electric) Pre-packaged fasteners (collated nails) Improved Productivity Used in many applications Power actuated fasteners Battery Powered Electric Nailer Collated Nails
- 51. Wood Screws Head type Phillips Slotted Square head Pan, flat, round, etc Sizing Gauge & Length Wire gauge (samples #8 & #10) Length in inches (and factions) Installation Hand screw driver “ Screw gun”, or drill Holding power Tighter, stronger than nails Can be “backed” out, & reinserted Uses Cabinetwork Some framing applications Decking - better hold - less squeak Deck Screws Types of ‘Heads ’
- 52. Lag & Drywall Screws Lag Screws Large screws Square or octagonal head Installed w/ wrench Drywall screws Used to attach drywall Drywall Screws (Size, 1 ¼, 1 5/8, 2 “) Screw Gun - Fast, Wood or Metal
- 53. Bolts Heavier structural connections COMMONLY USED W/ TIMBER CONSTRUCTION Sizes 1/4 inch to 1 inch+ LENGTH; ABOUT ANY (PRACTICALLY 10-12”) Types Machine SQUARE OR OCTAGONAL HEAD USED WITH WASHER Carriage ROUND BUTTON HEAD SQUARE SHANK INHIBITS TURNING Washers DISTRIBUTE THE COMPRESSIVE FORCE
- 54. Toothed Plates Sheet metal plate w/ numerous teeth Used with roof & floor trusses Pressed into members Very effective fasteners
- 55. Sheet Metal Framing Devices Light Wood Framing Joist Hangers Framing anchors Angle anchors Rafter anchor Heavy Timber or Laminated Framing
- 56. Widely used in the manufacture of wood products Wood panels Laminated wood Cabinetry On Site Uses Floor sheathing Base (sole) plates Wall panels Paneling (where there is a need for concealed fasteners) Increase stiffness, eliminate “squeak Adhesives
- 57. Additional Resources The Encyclopedia of Wood by: Aidan Walker Check out course website: Articles from Fine Homebuilding Magazine Website links
Editor's Notes
- #8: Thickness - “Nominal” < 2 inches - Boards FRAMING LUMBER - MOST 2 to 4 inches - Dimension Lumber = to or > 5 inches - Timbers Widths - “Nominal” Framing Lumber - 2, 4, 6, 8, 10, 12 inches WHY NOT Typically WIDER??? Finish /lumber - 1 inch (typ.)
- #9: Nominal not equal to “Actual” dimensions LUMBER “SAWN” Close to Nominal Then dried and surfaced Up to 6 inches - actual is 1/2 inch less Greater than 6 inches - actual is 3/4 inch less WHY THE “BREAK AT 6”??? MORE DISTORTION & SHRINKAGE TO ACCOMMODATE DURING SURFACING
- #10: Typically; Two (2) foot increments Sizes; 8’, 10’, 12’, 14’, & 16’ WHY NOT Typically LONGER??? Exceptions; 93 inch studs WHY 93 INCHES??? Special order lengths
- #12: Established by American Plywood Association (APA) Standards based on; Structural adequacy Dimensional Stability UNDER VARYING MOISTURE CONDITIONS Durability of Adhesive
- #20: Lamination Process SELECT LUMBER, GRADE JOINTS - FINGER OR SCARF ADHESIVES BASED ON EXPECTED MOISTURE Why Laminate? Create a size not available naturally Create Shapes ARCHES, CURVES, ETC. Improved Quality PROCESS CONTROLLED DEFECTS REMOVED / CONSIDERED GRAIN DIRECTION CONTROLLED USES CHURCHES LARGE RESIDENTIAL LODGES, RESTAURANTS
- #25: http://www.socalgas.com/construction/builders/Builders%20Resource%20Guide/Engineered%20Wood%20Wall%20Framing.htm
- #29: Uses FLOORS & ROOFS Sizes Typically, 9-1/2” TO 24 “ DEEP LENGTH UP TO 40 FEET+ Composition & cost TOP & BOTTOM - LUMBER OR Laminated WEB - OSB, PLYWOOD COST - COMPARABLE TO 2x
- #34: Why Panelize? More “controlled” product (strength, shrinkage, etc.) Efficient use of forest products Increase labor productivity Types Plywood Composite panels Veneered panels
- #35: Thin layers of veneer glued together VENEERS - ROTARY CUT Odd number of veneers Alternating direction of veneers Face veneers parallel USES SAME AS OSB EXPOSED/PAINTED SURFACES FORMWORK COST MORE THAN OSB
- #37: Based on the smoothness & integrity of the veneers Classifications; A, B, C (plugged), C, D B and better sanded smooth Price Variances (2001) 23/32 Exterior A/C = $31 per panel 23/32 Exterior B/C = $20 per panel MOST FORMWORK B/C FINISH AREAS MAY REQUIRE “A”
- #39: INTRODUCED IN THE EARLY 80’s GETTING WIDESPREAD USE Long strand like wood particles Alternate grain orientation (3-5 layers) Compressed / glued Strongest of the Non-veneered WHY IS IT THE STRONGEST??? ORIENTATION OF STANDS Generally more economical than Plywood Uses; Sheathing for floor, roofs, & siding WHY IS IT GETTING WIDESPREAD USE??? STRUCTURALLY SOUND ECONOMICAL - SUBBSTITUTE FOR PLYWOOD NEW GROWTH TREES
- #42: Combustibility FIRE RETARTANT IMPREGNATED UNDER PRESSURE Decay & Insect PRESSURE IMPREGNATED UP TO 30 YEAR LIFE TYPES CREOSOTE PENTACHOROPHENOL - OILY, CAN’T PAINT WATERBORNE SALTS - GREENISH - CAN PAINT Chromated Copper Arsenate (CCA) being phased out HIGH MOISTURE USES – WHY NOT USE DECAY RESISTANT WOODS??? (CEDAR, REDWOOD, CYPRESS) COST & STRENGTH
- #45: Common flat heads, used mostly for structural connections Finish Nails virtually headless, finish woodwork Common - Used for Framing, Large Shank & Head Box - Smaller Shank, less chance for splitting wood, Used Shingles, Rough Casings Casing, Finish, Brad - Finish Components, Sink Head Deformed Shank - Very Hard to Remove, DW & Flr. Concrete - Masonry & Concrete Cut - Finish Flooring - SQ Head Reduces Cracking Roofing - One of Many, Some Have lead/Rubber Washers
- #48: Size - Measured in “pennies” (Price of 100 nails long ago) Corresponding Lengths Same for Common & Finish Most Common Light Frame Nails - 16d for 2”, 10D AND 8D Coatings Bright/ Plain uncoated steel MOST COMMON USED - NON CORROSIVE OR CONCEALED CONDITION Corrosion-resistant “ EXPOSED TO WEATHER RUST OR STAIN LUMBER GALVANIZED, ALUM., SS Resin/Vinyl Decrease Drive & Increase Holding This nail has a smaller shaft – commonly called a ‘sinker’
- #50: Anchorage Face - Perpendicular to Grain End - Parallel Toe - Angle to Grain Which Has the Most Holding Power??? Which is most common???
- #51: APPLICATIONS FRAMING SHEATHING ROOFING
- #52: “ Head” type PHILLIPS SLOTTED SQUARE HEAD PAN, FLAT, ROUND, ETC. Sizing - Gauge & Length WIRE GAUGE (SAMPLES #8 & #10) LENGTH IN INCHES (AND FACTIONS) Installation HAND SCREW DRIVER “ SCREW GUN”, OR DRILL HOLDING POWER TIGHTER, STRONGER THAN NAILS CAN BE “BACKED” OUT, & REINSERTED Uses CABINETWORK SOME FRAMING APPLICATIONS DECKING - BETTER HOLD - LESS SQUECK
- #53: Lag Screws Large screws Very LARGE Screws, Wrench, ¼ “@ 2-6 in., ½ to 10” FOR HEAVIER STRUCTURAL CONNECTIONS Square or octagonal head Installed w/ wrench Drywall screws Used to attach drywall Drywall Screws (Size, 1 ¼, 1 5/8, 2 “, Screw Gun - Fast, Wood or Metal,
- #54: Heavier structural connections Sizes 1/4 inch to 1 inch+ LENGTH; ABOUT ANY (PRACTICALLY 10-12”) Types Machine SQUARE OR OCTAGONAL HEAD USED WITH WASHER Carriage ROUND BUTTON HEAD SQUARE SHANK INHIBITS TURNING Washers DISTRIBUTE THE COMPRESSIVE FORCE
- #56: NUMEROUS TYPES AND SHAPES MOST COMMON - JOIST HANGER LIGHT WOOD FRAMING - ATTACHED WITH SCREWS OR NAILS HEAVY TIMBER - ATTACHED WITH BOLTS / LAGS
- #57: ON SITE LESS USES BECAUSE OF NEED TO CLAMP USES FLOOR SHEATHING BASE (SOLE) PLATES WALL PANELS PANELING (WHERE THERE IS A NEED FOR CONCEALED FASTENERS) INCREASE STIFFNESS, ELIMINATE “SQUEAK”