chapter 1: building materials. how much should the “snow load” be in cordova alaska?
TRANSCRIPT
Chapter 1: Building Materials
How much should the “snow load” be in Cordova Alaska?
Why do we need to learn about the various types of building materials available for construction?
Why do we need to learn about the various types of building materials available for construction?
Objectives
• Describe the hardwood and softwood classifications.
• Define moisture content (M.C. and E.M.C.).• Identify common defects in lumber.• Define lumber grading terms.• Calculate lumber sizes according to established industry
standards.• Explain plywood, hardboard, and particleboard grades
and uses.• Identify nail types and sizing units.
Objectives
• List precautions to observe while working with treated lumber.
• Identify types of engineered lumber and list their uses and advantages.
• Discuss the uses of metal structural materials and describe their advantages/disadvantages.
• Identify a variety of metal framing connectors and indicate where each is used.
LumberLumber is the Name given to Natural or
Engineered Products of the Sawmill
- Boards
- Studs
- Timbers
- Post & Beams
Wood Structure
Kinds of Wood• Softwoods – Conifers
• Hardwoods – Deciduous
Kinds of Wood• Softwoods – Conifers
• Hardwoods – Deciduous
Cutting Lumber
Moisture Content (M.C.)• MC = % of oven dry weight
– Framing: 15%– Cabinet and Furniture: 7%-10%
Equilibrium MoistureContent (EMC)
• Molecules of water are constantly leaving and returning to the wood surface. If the same number of molecules of water return to as leave from the surface an equilibrium condition exists. Since the wood is neither gaining or losing water it is said to have reached an equilibrium moisture content, or EMC.
How is Lumber Dried?
• What process is best?
Lumber Defects
Lumber• Softwood Grades: Boards (e.g., Finish –
Prime), Dimension (Light Framing – Economy), & Timbers (No.1). See Fig 1.5– Stress Values (MSR)
• Hardwood Grades: First and Seconds (FAS), Selects, No. 1 Common.
• Lumber Sizes: Nominal (2x4) and Dressed (1 ½ X 3 ½)
• Metric Lumber
Board Feet
No. pcs. x T” x W” x L’
2
Can you buy metric lumber?
BD Ft. =
Square Feet
How Much Extra Do You Add to Your Job?.
Panel Materials• Plywood
• Composite Plywood
• Non-veneered Panels– Particle Board– Fiberboard– Oriented Strand Board
Why 15/32? Not ½”?
Span Ratting:•32” for Roofs•16” for Subfloors
Hardwood & Plywood Grades
• Grading for Faces and Backs: No. 1, 2, or 3
• G2S – Good two sides or (G1S)
• Lumber or Veneer Core
Particle BoardWood Flakes, Chips, and Shavings
Bonded Together.
HardBoard• Refined Wood Fibers
• Tempered
• One or two sides smooth
Oriented Strand Board (OSB)
• Flakes of Wood
• Bonded under heat and pressure.
• Many Applications
Wood Treatments• Why Treat Wood?
• Pressure Treated Wood
• Three types of Liquid Preservatives– Waterborne (CCA, CZC, etc.)– Oilborne– Creosote
Engineered Lumber• Engineered Structural Lumber is made up
of Laminated Veneer Lumber (LVL), manufactured wood I-beams, and manufactured trusses.
• Using Engineered Structural Lumber products reduces demand on forests by using wood waste or small dimensional lumber in place of larger lumber.
Open-Web Truss• …
Nonwood Materials• Metal Framing Members
• Gypsum and Metal Lath
• Wallboard and Sheathing
• Insulating Boards, baths, and loose insulation
Insulation
Strapping, Ties, & Hangers
Metal Fasteners
• Nails – 5 basic Types (penny – d)
• Many types of special nails (e.g., spiral)
• Nail Coatings: zinc, cement, resin
• Wood Screws
Concrete
Adhesive Bonding Agents
• Glues
• Adhesive Cements
• Mastics
THE END
Building materials must
be properly used – using
“shoddy” construction practices is dangerous!