1. Unit 1 Building Materials
Modern carpentry
Building construction

2. Building materials
Many different types of materials go into the construction of a modern residence. A carpenter needs to be familiar with these materials. All of these materials have special properties that makes it suitable for it’s application. This includes natural and man made (composites) products.

3. Common Construction materials
Sawed lumber
Engineered lumber
Plywood
Particleboard, Hardboard, and Waferboard
Steel and Aluminum
Metal fasteners
Concrete
Wood and non wood materials for shingles and flooring
Adhesives and Sealers
Gypsum board and other interior covering

4. Sawed Lumber
Lumber is one of the greatest natural resources in the world today. Because it is easy to saw and rework on the job site makes it one of the best choices for residential construction.

5. Sawed Lumber
Once a tree is harvested and cut in to uniform thicknesses, width, and length it becomes lumber.
Lumber is the name given to natural or engineered products of a sawmill.

6. Lumber includes
Boards used for flooring, sheathing, paneling and trim.
Dimension lumber used for sills, plates, studs, joists, rafters, and other framing members
Timbers used for posts, beams, and heavy stringers.

7. Wood Structure and Growth
The growing parts of a tree are:
The tips and roots
The leaves
The layer of cells just under the bark called the Cambium

8. Wood Structure and Growth
nutrients and water absorbed by the roots travels in a layer under the bark known as sap wood to the leaves, and combines with carbon dioxide from the air.
through a process called photosynthesis, sunlight changes these elements in to food. The sap caries this food back to various parts of the tree.

9. Annual rings
The rings of a tree are made up of two layers: spring wood and summerwood.
Growth of the rings takes place in the cambium layer in the spring and fall.
In the spring growth is fastest and slows during the summer and fall seasons

10. Annual rings

11. Kinds of Wood Lumber is either softwood or hardwood.
Softwoods come from the evergreen, or needle-bearing trees. Another name for evergreen is conifers because many of them bear cones.
Hardwood comes from broadleaf (deciduous) trees that loose their leaves at the end of the growing season.

12. Kinds of Wood Soft woods Douglas Fir Southern Pine Western Larch
Hemlock
White Fir
Spruce
Ponderosa Pine
Western Red Cedar
Redwood
Hardwoods
Maple
Oak
Walnut
Cherry
Birch
Beech
Willow
Elm
Mahogany

13. Kinds of Wood
When it comes to the rough framing of residential construction softwood is more commonly used with Douglas Fir being most commonly used.
Hardwoods are most commonly used for finishing such as; flooring, trim, casing, cabinets, and furniture.

14. Moisture Content and Wood
A piece of wood will give off or take on moisture from the air around it until the moisture in the wood is ballanced with that in the air.
As the moisture in wood changes so does the wood size and shape.
The average moisture content of lumber in an homes is 8%.

15. Moisture Content and Wood

16. Lumber Defects
A defect is an irregularity occurring in or on wood that reduces its strength, durability, or usefulness.
Types of defects
Knot
Split and Checks
Wane
Blue Stain
Decay
Holes
Warp

17. Lumber Defects
Knots are caused by an embedded branch or limb. Knots reduce the strength of the lumber.
Split and Checks is the separation of the wood fibers which run along the grain across the annual growth rings.
Wane is the presence of bark or the absence of wood along the edge of a board. Wane forms a bevel and may reduce width.

18. Lumber Defects
Blue Stain is the discoloration caused by a mold like fungus, blue stain has little or no affect on wood strength.
Decay the disintegration of wood fibers due to fungi, decay is often difficult to recognize in its early stages.

19. Lumber Defects
Holes are caused by handling equipment or boring insects and worms. Severe holes can weaken lumber greatly.
Warp any variation from a true plane surface. Warp may include any one or a combination of Cup, Bow, Crook, and Twist

20. A; Crook B; Twist C; Bow

21. Wood Grades
Wood grades are divided into two categories one for soft woods and another for hard woods.
The carpenter must understand that quality construction does not require that all lumber be of the best grade.
In a given structure, several grades may be appropriate.
The key to good economical construction is matching the proper grade with its function

22. Lumber size
When listing and calculating the size and amount of lumber, the nominal size is always used. Ex 2x4, 2x6, 2x8, ect.
The nominal size is the lumbers rough unfinished size.
The dressed size is less than the nominal size as a result of seasoning and surfacing.
Dressed sizes are enforced across North America and must be maintained through the industry.

24. Panel Material
Panel materials for construction purposes are constructed in several different ways.
Plywood
Softwood Plywood Grades
Wafer board
Oriented Strand Board

25. Plywood
Plywood is constructed by gluing together a number of layers (plies) of wood.
Each layers wood grain is turned at a right angle to the one before it.
There is always an odd number of layers so the panel is balanced. This is so the grain runs in the same direction on either side of the sheet.
The thicker the panel the more layers required.

26. Exterior plywood Exterior ply wood is bonded using a waterproof glue.
It can be used for siding, concrete forms, and other constructions where it will be exposed to the weather or excessive moisture.

27. Softwood plywood grades
Softwood plywood is for general construction purposes
It must be noted that many species of softwoods are used in making plywood.
There are 5 separate plywood groups based on stiffness and strength.
Group #1 is the stiffest and strongest.

28. Waferboard
Is produced from High quality flakes (chips) of wood that is about 1 ½” square.
The chips are bonded together under heat and pressure with resins.
The 4’x8’ sheets range in thicknesses from ¼” to 1 1/8”

29. Oriented Strand Board (OSB)
Similar in appearance to waferboard and also made up of wood fibers (chips).
The fibers of OSB are placed in successive layers arranged at right angles to each other.

30. Engineered Lumber
It once took more than 80 years to saw mill size. Tree farming has shortened this to 27 years but has had a great affect on the spacing of the annual rings.
Lumber today have annual rings further apart making it weaker and not suitable for spanning long distances.

31. Engineered Lumber Some engineered lumbers include
Laminated-Veneer Lumber (LVL)
Glue-Laminated Beams
Wooden I-Beams
Open-Web Trusses

32. Laminated-Veneer Lumber (LVL)
Constructed much like plywood with many lavers of wood.
Each laver is 8” wide and 1/8” thick
Each laver is coated with glue, stacked, placed under pressure and heated until dry

33. Glue-Laminated Beams
Glue-laminated beams are made from a stack of 2x4 or 2x6 to form a beam up to 30” deep.
These beams are used when long distances must be spanned.

34. Glue-Laminated Beams

35. Wooden I-Beams
Wood I-Beams are constructed of laminated veneer lumber while the web is made of plywood or oriented strand board (OSB)
Wooden I beams are light, strong, and straight.
They are often used as floor Joists

36. Wooden I-Beams

37. Open-Web Trusses
Open-web trusses are also often used in place of floor Joists.
They are used when long spans are demanded.
They are constructed from solid 2x4s

38. Open-Web Trusses

39. Steel framing
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