1. Lesson A3–8: Selecting Lumber Selecting Lumber

2. Next Generation Science/Common Core Standards Addressed! CCSS.ELALiteracy.RST.9 ‐ 10 Determine the meaning of symbols, key terms, and other domain ‐ specific words and phrases as they are used in a specific scientific or technical context relevant to grades 9–10 texts and topics..4 CCSS.ELALiteracy.RST.9 ‐ 10 Determine the meaning of symbols, key terms, and other domain ‐ specific words and phrases as they are used in a specific scientific or technical context relevant to grades 9–10 texts and topics..4 CCSS.ELALiteracy.RST.11 ‐ 12.4 Determine the meaning of symbols, key terms, and other domain ‐ specific words and phrases as they are used in a specific scientific or technical context relevant to grades 11–12 texts and topics. CCSS.ELALiteracy.RST.11 ‐ 12.4 Determine the meaning of symbols, key terms, and other domain ‐ specific words and phrases as they are used in a specific scientific or technical context relevant to grades 11–12 texts and topics. HSNQ.A.1 Use units as a way to understand problems and to guide the solution of multi ‐ step problems; choose and interpret units consistently in formulas; choose and interpret the scale and the origin in graphs HSNQ.A.1 Use units as a way to understand problems and to guide the solution of multi ‐ step problems; choose and interpret units consistently in formulas; choose and interpret the scale and the origin in graphs

3. Agriculture, Food and Natural Resource Standards Addressed! PST.04.03. Follow architectural and mechanical plans to construct, maintain and/or repair AFNR structures (e.g., material selection, site preparation and/or layout, plumbing, concrete/ masonry, etc.). PST.04.03. Follow architectural and mechanical plans to construct, maintain and/or repair AFNR structures (e.g., material selection, site preparation and/or layout, plumbing, concrete/ masonry, etc.). PST.04.03.01.b. Analyze and assess samples of materials or products for quality and efficiency of workmanship. PST.04.03.01.b. Analyze and assess samples of materials or products for quality and efficiency of workmanship.

4. Bell Work/ Student Learning Objectives Explain how to produce and process lumber and wood products. Explain how to produce and process lumber and wood products. Discuss the grading and selection of lumber. Discuss the grading and selection of lumber. Explain the process of sizing, buying, and storing lumber. Explain the process of sizing, buying, and storing lumber.

5. Terminology Bending strength Bending strength Board feet Board feet Common boards Common boards Compression strength Compression strength Dimension lumber Dimension lumber Dressed lumber Dressed lumber Factory or shop lumber Factory or shop lumber Green lumber Green lumber Hardboard Hardboard Hardness Hardness Hardwood Hardwood Kiln-dried lumber Kiln-dried lumber Linear feet Linear feet Nominal or rough lumber Nominal or rough lumber Paneling Paneling Particle board Particle board Pegboard Pegboard Plain sawing Plain sawing Plywood Plywood Quarter sawing Quarter sawing

6. Terms Seasoning Seasoning Select or finish boards Select or finish boards Softwood Softwood Stiffness Stiffness Structural lumber Structural lumber Toughness Toughness Veneer Veneer Wafer board Wafer board Worked lumber Worked lumber Yard lumber Yard lumber

7. Interest Approach Show samples of various sizes of lumber and examples of wood products such as plywood, particle board, and wafer board. Show samples of various sizes of lumber and examples of wood products such as plywood, particle board, and wafer board. Ask students questions to spark their interest in learning about selecting, grading, buying, and storing lumber. Ask students questions to spark their interest in learning about selecting, grading, buying, and storing lumber.

8. Interest Approach What happens between cutting down a tree and you buying the wood as lumber? What happens between cutting down a tree and you buying the wood as lumber? How is lumber graded and stored? How is lumber graded and stored? How can you determine which type of lumber to buy? How can you determine which type of lumber to buy?

9. Lumber Production and Processing After trees are cut down they are transported to the sawmill. After trees are cut down they are transported to the sawmill. The logs are soaked until sawing time to prevent checking, cracking, and warping. The logs are soaked until sawing time to prevent checking, cracking, and warping.

10. Lumber Production and Processing After removing the bark, the wood is cut into standard lengths and widths and is referred to as lumber. After removing the bark, the wood is cut into standard lengths and widths and is referred to as lumber. Logs are either regular/plain-sawed or quarter-sawed. Logs are either regular/plain-sawed or quarter-sawed.

11. Plain-Sawing Plain sawing: Cutting the log on a tangent to the growth rings Plain sawing: Cutting the log on a tangent to the growth rings Is faster with less waste resulting in lower cost lumber. Is faster with less waste resulting in lower cost lumber. Produces a flat or slash-grained lumber that is used for most buildings. Produces a flat or slash-grained lumber that is used for most buildings.

12. Plain-Sawing

13. Quarter-Sawed Lumber Quarter sawing: Cutting the log perpendicular to the growth rings Quarter sawing: Cutting the log perpendicular to the growth rings Results in lumber less likely to warp, shrink, and swell. Results in lumber less likely to warp, shrink, and swell. Since quarter-sawed edge or vertical grained boards have a prettier grain, they are often used to make furniture. Since quarter-sawed edge or vertical grained boards have a prettier grain, they are often used to make furniture.

14. Quarter-Sawed Lumber

15. Drying Lumber After the lumber is cut, it is ready to be dried. After the lumber is cut, it is ready to be dried. Seasoning: Process of drying lumber to the point where it is ready to use. Seasoning: Process of drying lumber to the point where it is ready to use. Green lumber: Freshly cut lumber with 20 percent or more moisture. Green lumber: Freshly cut lumber with 20 percent or more moisture.

16. Drying Lumber Lumber can be stacked outside with spacers to allow air flow between layers. Lumber can be stacked outside with spacers to allow air flow between layers. Air drying takes from one to three months and typically reduces moisture content to 15 percent. Air drying takes from one to three months and typically reduces moisture content to 15 percent.

17. Drying Lumber Kiln-dried lumber uses a large oven or kiln to dry the lumber to 6 to 12 percent moisture. Kiln-dried lumber uses a large oven or kiln to dry the lumber to 6 to 12 percent moisture. Starting with high steam and low heat the kiln gradually adjusts to low steam and high heat to remove moisture without creating cracks in the lumber. Starting with high steam and low heat the kiln gradually adjusts to low steam and high heat to remove moisture without creating cracks in the lumber.

19. Drying Lumber After drying, the lumber in some cases is used rough, also referred to as unmilled or unplaned. After drying, the lumber in some cases is used rough, also referred to as unmilled or unplaned. Dressed lumber is smoothed and given uniform dimensions by running it through a planer. Dressed lumber is smoothed and given uniform dimensions by running it through a planer.

21. Dried and Planed Lumber Can be processed into a variety of wood products such as: Can be processed into a variety of wood products such as: Beveled siding, Beveled siding, Tongue-and-groove flooring, Tongue-and-groove flooring, Trim, Trim, Molding, Molding, Etc.. Etc..

22. Plywood: Wood product made of a series of plies or layers (3, 5, or 7) glued together with the grains of adjacent layers arranged at right angles to each other to form a 4×8 sheet. Wood product made of a series of plies or layers (3, 5, or 7) glued together with the grains of adjacent layers arranged at right angles to each other to form a 4×8 sheet. By gluing layers so that the grain runs in opposite directions the strength is maximized. By gluing layers so that the grain runs in opposite directions the strength is maximized.

24. Particle Board 4×8 sheet made by gluing wood chips, splinter, and sawdust together. 4×8 sheet made by gluing wood chips, splinter, and sawdust together. Because it is hard and brittle, it is used under countertops and in some furniture. Because it is hard and brittle, it is used under countertops and in some furniture.

26. Particle Board While particle board is cheaper than plywood, it needs to be cut with a carbide-tipped blade and warps quickly when it gets wet. While particle board is cheaper than plywood, it needs to be cut with a carbide-tipped blade and warps quickly when it gets wet.

27. Waferboard Also known as OSB board and chip board Also known as OSB board and chip board Made by gluing wood chips to form 4×8 sheets. Made by gluing wood chips to form 4×8 sheets. Since it is cheaper and more water resistant, wafer board is replacing plywood as roof sheathing and subflooring. Since it is cheaper and more water resistant, wafer board is replacing plywood as roof sheathing and subflooring.

29. Hardboard Made by gluing wood fibers into sheets. Made by gluing wood fibers into sheets. Since it is hard and brittle, it should be cut with a carbide-tipped blade and it does not hold nails well. Since it is hard and brittle, it should be cut with a carbide-tipped blade and it does not hold nails well. May be used as tabletops or shaped in long boards to use as siding. May be used as tabletops or shaped in long boards to use as siding.

31. Pegboard Pegboard: Hardwood with a series of uniformly sized and shaped holes. Pegboard: Hardwood with a series of uniformly sized and shaped holes. Pegboard is useful as a hand tool organizer. Pegboard is useful as a hand tool organizer. Peg-board hooks of various sizes are available at most hardware stores. Peg-board hooks of various sizes are available at most hardware stores.

33. Paneling 1/8 or ¼ inch sheet of wood or hardboard with a wood grain surface. 1/8 or ¼ inch sheet of wood or hardboard with a wood grain surface. Inexpensive paneling may be hardboard with wood grain contact paper on the surface. Inexpensive paneling may be hardboard with wood grain contact paper on the surface.

35. Veneer Thin layer of material that is glued to an inferior quality material. Thin layer of material that is glued to an inferior quality material. While high quality furniture is generally solid wood, low cost furniture is often particle board with a veneer wood grain surface layer. While high quality furniture is generally solid wood, low cost furniture is often particle board with a veneer wood grain surface layer.

37. Anticipated Problem: How is lumber graded and selected for use?

38. Lumber Grading and Selection Wood for lumber is divided into two broad categories, “softwood” and “hardwood”. Wood for lumber is divided into two broad categories, “softwood” and “hardwood”. Refers not to the hardness of the wood, but to the type of tree they come from. Refers not to the hardness of the wood, but to the type of tree they come from.

39. Lumber Grading and Selection Softwood: Lumber cut from coniferous (cone-bearing) evergreen trees with needle-like leaves. (Ponderosa Pine) Softwood: Lumber cut from coniferous (cone-bearing) evergreen trees with needle-like leaves. (Ponderosa Pine) Hardwood is lumber cut from broad- leaved (deciduous) trees that drop their leaves in the fall. (Oak, Pecan) Hardwood is lumber cut from broad- leaved (deciduous) trees that drop their leaves in the fall. (Oak, Pecan)

40. Lumber Grading and Selection Fine furniture is typically made from hardwood. Fine furniture is typically made from hardwood. Since construction lumber is generally softwood this unit will focus on softwood grading. Since construction lumber is generally softwood this unit will focus on softwood grading.

41. Softwood Grading Softwood grading is based on: Softwood grading is based on: Appearance, Appearance, Strength, or Strength, or Combination of the two. Combination of the two.

42. Softwood Grading Defects which can affect both appearance and strength include: Defects which can affect both appearance and strength include: knots, knots, checks, checks, splits, splits, decay, decay, stains, stains, insect holes insect holes

43. Softwood Grading Softwood grading classifies lumber according to use: Softwood grading classifies lumber according to use: Yard lumber, Yard lumber, Structural lumber, and Structural lumber, and Factory or shop lumber. Factory or shop lumber.

44. Yard Lumber Lumber less than five inches thick Lumber less than five inches thick Used for ordinary construction and general building purposes. Used for ordinary construction and general building purposes.

45. Structural lumber Two inches or more in nominal thickness and width Two inches or more in nominal thickness and width Stress tested and used as: Stress tested and used as: Joists,-Beams, Joists,-Beams, Stringers,-Posts, Stringers,-Posts, Timbers, -Truss members. Timbers, -Truss members. For the most part, it is wider and thicker than dimension lumber. For the most part, it is wider and thicker than dimension lumber.

46. Factory or shop lumber Used in: Used in: Doors, Doors, Window sashes, Window sashes, Foundry patterns, and Foundry patterns, and General cut-up purposes. General cut-up purposes. Often referred to as molding Often referred to as molding

47. Select or Finish Boards While blueprints may specify stress rated structural lumber for some framing components, most building is done with yard lumber. While blueprints may specify stress rated structural lumber for some framing components, most building is done with yard lumber. Yard lumber includes select or finish boards, common boards, and dimension lumber. Yard lumber includes select or finish boards, common boards, and dimension lumber.

48. Select or Finish Boards Select or finish boards: Graded A through D based on appearance. Select or finish boards: Graded A through D based on appearance. Typically one inch thick (1 × 4,1 ×6,etc.) Typically one inch thick (1 × 4,1 ×6,etc.) Used as an inside surface to be coated with varnish or paint. Used as an inside surface to be coated with varnish or paint.

49. Common Boards: One inch thick, One inch thick, 2 to 12 inches wide 2 to 12 inches wide Graded on a combination of appearance and strength from number 1 common to number 5 common. Graded on a combination of appearance and strength from number 1 common to number 5 common.

50. Dimension Lumber: Two to five inches thick Two to five inches thick Two inches or more wide Two inches or more wide Graded on strength and stiffness. Graded on strength and stiffness. Dimension lumber grades are: Dimension lumber grades are: Construction, Construction, Standard, Standard, Utility, Utility, Economy, and Economy, and Economy stud. Economy stud.

51. Graded Lumber Graded lumber will have a grade mark that includes: Graded lumber will have a grade mark that includes: Grade, Grade, Moisture content, Moisture content, Species of the tree, Species of the tree, Mill where processing was done, and Mill where processing was done, and Certification mark indicating the association that graded the lumber. Certification mark indicating the association that graded the lumber.

53. Plywood Grade is based on the outer plies. Grade is based on the outer plies. Interior plies are grade D. Interior plies are grade D. Grade is based on the presence of knots, knot holes, and surface plugs. Grade is based on the presence of knots, knot holes, and surface plugs. Exterior plywood has waterproof glue Exterior plywood has waterproof glue

54. Plywood Interior plywood has only water resistant glue. Interior plywood has only water resistant glue. Application with only one exposed surface can be graded A–D or A–C. Application with only one exposed surface can be graded A–D or A–C. Signs and cabinets need A–A with two good sides. Signs and cabinets need A–A with two good sides. Roof sheathing is usually construction grade plywood (CDX). Roof sheathing is usually construction grade plywood (CDX).

55. Selecting Grade to Buy Use the lowest quality of lumber suitable for the purpose.(save $) Use the lowest quality of lumber suitable for the purpose.(save $) Inexperienced buyers should depend on the advice of an experienced, reliable lumber yard employee to make grade purchase decisions. Inexperienced buyers should depend on the advice of an experienced, reliable lumber yard employee to make grade purchase decisions.

56. Matching Lumber to job Requires a knowledge of the characteristics of each species of wood. Requires a knowledge of the characteristics of each species of wood. What to look for when: What to look for when: Siding for a house: Siding for a house: Good nailing and weather resistant qualities. Good nailing and weather resistant qualities. House framing members: House framing members: Strength and stiffness. Strength and stiffness.

57. Matching Lumber to job Furniture construction: Furniture construction: Attractive appearance, freedom from blemishes and flaws, desirable wood grain, hardness, and resistance to warping are important. Attractive appearance, freedom from blemishes and flaws, desirable wood grain, hardness, and resistance to warping are important.

58. Matching Lumber to job White woods (white pine, fur, and spruce) and yellow pine: Most popular species used in construction. White woods (white pine, fur, and spruce) and yellow pine: Most popular species used in construction.

60. Properties of Wood Good understanding of wood properties is essential for intelligent lumber selection. Good understanding of wood properties is essential for intelligent lumber selection. Properties Include: Properties Include: Hardness Hardness Bending strength Bending strength Stiffness Stiffness Compression strength Compression strength Toughness Toughness

61. Hardness Wood is solid or firm, and will not dent or scratch easily. Wood is solid or firm, and will not dent or scratch easily. Weight of dry wood is a good indicator of its relative strength. Weight of dry wood is a good indicator of its relative strength. Freedom from warping and bowing is important. Freedom from warping and bowing is important. Ease of cutting and nail-holding power should be considered. Ease of cutting and nail-holding power should be considered.

62. Bending Strength Ability of lumber to be bent without breaking. Ability of lumber to be bent without breaking.

63. Stiffness Ability of wood to resist bending under load. Ability of wood to resist bending under load.

64. Compression Strength Ability of a piece of lumber to resist being mashed or squeezed together by weight applied against its ends. Ability of a piece of lumber to resist being mashed or squeezed together by weight applied against its ends.

65. Toughness Ability of the wood to withstand sudden shock. Ability of the wood to withstand sudden shock. Tough wood refuses to break when subjected to repeated shocks, jars, or blows Tough wood refuses to break when subjected to repeated shocks, jars, or blows

66. Anticipated Problem: How is lumber sized, purchased, and stored?

67. Sizing, Purchasing, and Storing Lumber May be purchased green (over 20 percent moisture), air dried, or kiln dried. May be purchased green (over 20 percent moisture), air dried, or kiln dried. They may be rough, dressed, or worked lumber. They may be rough, dressed, or worked lumber. Nominal, or rough lumber: Lumber as it comes from the saw (unplaned). Nominal, or rough lumber: Lumber as it comes from the saw (unplaned).

68. Sizing, Purchasing, and Storing Lumber Most lumber is planed before it is sold. Most lumber is planed before it is sold. Planed lumber is also called: Planed lumber is also called: Surfaced, Surfaced, Dressed, and Dressed, and Milled. Milled.

69. Sizing, Purchasing, and Storing Lumber The difference between nominal and dressed dimensions of lumber is the result of: The difference between nominal and dressed dimensions of lumber is the result of: Planing, Planing, Shrinkage that occurs during drying. Shrinkage that occurs during drying.

70. Sizing, Purchasing, and Storing Lumber Worked lumber: Wood that has been: Worked lumber: Wood that has been: Shaped (trim), Shaped (trim), Matched (tongue-and-groove), or Matched (tongue-and-groove), or Patterned (molding). Patterned (molding).

71. Actual vs. Nominal Dimensions Project planner uses the actual planed dimensions (¾×3½, 1½×7¼, etc.) to determine the number and length of boards needed Project planner uses the actual planed dimensions (¾×3½, 1½×7¼, etc.) to determine the number and length of boards needed Nominal dimensions (2×4, 1×6, etc.) are used when ordering lumber. Nominal dimensions (2×4, 1×6, etc.) are used when ordering lumber.

72. Actual vs. Nominal Dimensions Softwood nominal widths are 2, 3, 4, 6, 8, 10, and 12 inch. Softwood nominal widths are 2, 3, 4, 6, 8, 10, and 12 inch. Standard available lengths are even feet from 6 to 20. Standard available lengths are even feet from 6 to 20. Lumber with nominal thickness of 1 inch is actually ¾ inches while 2 inch lumber is actually 1½ inch thick as a result of planning. Lumber with nominal thickness of 1 inch is actually ¾ inches while 2 inch lumber is actually 1½ inch thick as a result of planning.

73. Actual vs. Nominal Dimensions To find the actual width for nominal widths of 6 inches or less drop ½ inch. To find the actual width for nominal widths of 6 inches or less drop ½ inch. For nominal widths of over 6 inches drop ¾ inch to find the actual width. For nominal widths of over 6 inches drop ¾ inch to find the actual width.

74. Board Sizes Common boards and dimension lumber is bought and sold by the board foot or per thousand feet. Common boards and dimension lumber is bought and sold by the board foot or per thousand feet. Board feet = thickness × width × length divided by 12. Board feet = thickness × width × length divided by 12. Molding and trim boards are sold by the linear feet or running feet, rather than board feet. Molding and trim boards are sold by the linear feet or running feet, rather than board feet.

75. Board Sizes Linear feet: is simply length in feet without regard to thickness or width. Linear feet: is simply length in feet without regard to thickness or width. Generally sold by the 4×8 sheet: Generally sold by the 4×8 sheet: Plywood, Plywood, Particle board, Particle board, Hard-board, Hard-board, Pegboard, and Pegboard, and Paneling are generally sold by the 4×8 sheet. Paneling are generally sold by the 4×8 sheet.

76. Board Sizes Thickness of these sheets vary through a range of ¼, 3 / 8,½,5 / 8, to ¾ inch. Thickness of these sheets vary through a range of ¼, 3 / 8,½,5 / 8, to ¾ inch.

79. Actual vs. Nominal Dimensions All of these materials are priced either by the square foot or by the sheet. All of these materials are priced either by the square foot or by the sheet. Other building materials, such as roofing, shingles and siding, are sold by “the square”. Other building materials, such as roofing, shingles and siding, are sold by “the square”. “The square” actually means 100 square feet of surface coverage. “The square” actually means 100 square feet of surface coverage.

80. Ordering Lumber Do not order large quantities of lumber long in advance of the time it will be needed. Do not order large quantities of lumber long in advance of the time it will be needed. If delivered lumber must be stored for a period of time, care should be taken to avoid: If delivered lumber must be stored for a period of time, care should be taken to avoid: Warping, Warping, Staining, and Staining, and Moisture absorption problems. Moisture absorption problems.

81. Ordering Lumber Lumber should be neatly stacked using stickers or spacers every few rows to allow air circulation. Lumber should be neatly stacked using stickers or spacers every few rows to allow air circulation. If stored outside: If stored outside: Keep the stack relatively level, Keep the stack relatively level, off the ground, and off the ground, and covered with moisture-resistant covering like plastic. covered with moisture-resistant covering like plastic.

83. Review How are lumber and wood products produced and processed? How are lumber and wood products produced and processed? How is lumber graded and selected of lumber? How is lumber graded and selected of lumber? How is lumber sized, bought, and store? How is lumber sized, bought, and store?

84. The End!