Building Materials, Fasteners, & Adhesives PDF

M I L L VA L L E Y C o n s t r u c t i o n L a b p r e s e n t s Building Materials, Fasteners, & Adhesives Wood and Lumber Session 2 After this presentation students should Objectives...

M I L L VA L L E Y C o n s t r u c t i o n L a b p r e s e n t s Building Materials, Fasteners, & Adhesives Wood and Lumber Session 2 After this presentation students should Objectives understand...  The parts of a tree trunk and their POINTS WE'LL DISCUSS functions  The differences between softwoods and hardwoods  The types of lumber, their characteristics, common defects, and how lumber is graded.  Introduction Why should we care? Wood is the most common construction material. Trees sawn into lumber results in different characteristics. It is necessary to understand these characteristics. Background What about trees?  Science Review  Wood Structure and Growth What is the structure?  Growth is rapid in the spring.  Growth slows in summer, and wood rings form.  The rings in the wood are called annular rings.  Counting the dark rings determines a tree’s age. - Section 2.1.1 Wood Structure and Growth What are the parts? Inner cells become heartwood; Sapwood carries the food and is less dense and strong Medullary rays* - Section 2.1.1 Wood Structure and Growth Matching Game G. Bark E. Medullary Rays C. Pith B. Annular Rings D. Cambium Layer F. Heartwood A. Sapwood  Review Question One 1. In the cross section of a tree, one year of tree growth is represented by one _____. a. cambium layer b. annular ring c. medullary ray d. lignin Module 27102 – Building Materials, Fasteners, and Adhesives  Review Question One Answer 1. In the cross section of a tree, one year of tree growth is represented by one _____. b. annular ring Module 27102 – Building Materials, Fasteners, and Adhesives Wood and Lumber Characteristics What is the difference between hardwoods and softwoods? HARDWOODS AND SOFTWOODS  Hardwood is from deciduous trees  Shed their leaves  Softwood is cut from coniferous trees (cone-bearing)  Don’t yearly shed needles (needle like leaves)  Hardwoods vs. Softwoods in actual use - Section 2.1.1  Lumber Characteristics What are the types of sawn lumber?  Plainsawn lumber- at angle of less than 45 degrees. - Section 2.1.2 Lumber Characteristics What are the types of sawn lumber?  Quarter sawn-at angle greater than 45 degrees - Section 2.1.2 Lumber Characteristics What are the defects of lumber? Defects can occur while the lumber is drying out. Defects affect the lumber’s appearance, strength, and use. - Section 2.1.3  Review Question Two 2. Which of the following defects do not occur naturally in wood? a. Checks b. Pitch streaks c. Knots d. Torn grain Module 27102 – Building Materials, Fasteners, and Adhesives  Review Question Two Answer 2. Which of the following defects do not occur naturally in wood? d. Torn grain Module 27102 – Building Materials, Fasteners, and Adhesives Lumber Characteristics What are the traits of lumber?  Crown: a board hump on one edge. Note: image is exaggerated  If crowned badly it can’t be used. ^ Crown should face upward when framing. Why do you think this is? - Section 2.1.3  Lumber Grading  Here are the components of a typical lumber stamp. A. Inspection association trademark B. Mill identification C. Grade designation D. Species identification E. Condition of seasoning at time of surfacing What does this tell me about it’s use? Section 2.1.5 Module 27102 – Building Materials, Fasteners, and Adhesives  Lumber Grading Answers (1 of 5) A. Inspection association trademark Section 2.1.5 Module 27102 – Building Materials, Fasteners, and Adhesives  Lumber Grading Answers (2 of 5) B. Mill identification Section 2.1.5 Module 27102 – Building Materials, Fasteners, and Adhesives  Lumber Grading Answers (3 of 5) C. Grade designation Section 2.1.5 Module 27102 – Building Materials, Fasteners, and Adhesives  Lumber Grading Answers (4 of 5) D. Species identification Section 2.1.5 Module 27102 – Building Materials, Fasteners, and Adhesives  Lumber Grading Answers (5 of 5) E. Condition of seasoning at time of surfacing Section 2.1.5 Module 27102 – Building Materials, Fasteners, and Adhesives ` Lumber Grading  Match each lumber grade stamp on the left with its appropriate definition on the right. 2. 3. Condition of seasoning at time of surfacing #5 1. Grade designation #3 Inspection association 5. trademark. #1 4. MC-15 = 15% S-Dry = 19% Mill identification #2 S-Grn = +19% #4 Species identification Section 2.1.5 Module 27102 – Building Materials, Fasteners, and Adhesives  Review Question Three 3. In the grading stamp shown above, the term “S-DRY” means that the lumber... a. has a maximum 15 percent moisture content b. has a moisture content over 19 percent c. contains a max of 19 percent moisture d. is made from standard greenwood Module 27102 – Building Materials, Fasteners, and Adhesives  Review Question Three 3. In the grading stamp shown above, the term “S-DRY” means that the lumber... c. contains a max of 19 percent moisture Module 27102 – Building Materials, Fasteners, and Adhesives  Review Question Four 3. In term “S-GRN” means that the lumber… a. is made from short-grain wood. b. contains MORE than 19 percent moisture c. should be painted with green primer d. is made from standard dry wood Module 27102 – Building Materials, Fasteners, and Adhesives  Review Question four Answer 3. In term “S-GRN” means that the lumber… a. is made from short-grain wood. b. contains MORE than 19 percent moisture c. should be painted with green primer d. is made from standard dry wood Module 27102 – Building Materials, Fasteners, and Adhesives Conclusion  We looked at the components of wood structure.  We identified the differences between softwoods and hardwoods  We saw that lumber is plain sawn or quarter sawn.  We learned how defects affect the appearance and strength of lumber.  We examined how lumber is graded. Congratulations!!! Read Sections 2.0.0-2.1.7 + “Self-Guided Learning” sections 1 & 2. 🪓🪚🪵 Module 27102 – Building Materials, Fasteners, and Adhesives