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1
Q

What are softwoods used for?

A

Structural wood products, finish trim, shingles and siding, flooring.

2
Q

What are hardwoods used for?

A

Fine trim, paneling, flooring, fine cabinet work, furniture.

3
Q

What is moisture content?

A

The amount of water present in wood. Described as the weight of the water in the wood as a percentage of the weight of the dry wood. Ranges from 30 to 200%.

4
Q

What is the equilibrium moisture content for exterior and interior wood in North America?

A

Exterior: 12%
Interior: 8%

5
Q

What is seasoning?

A

The extent of wood drying. Usually done at the sawmill by air-drying for months or by drying in kilns for several days. Kiln drying produces fewer distortions.

6
Q

When seasoned, how does wood change?

A

Longitudinal shrinkage is negligible. Radial shrinkage is larger by comparison. Shrinkage around the circumference (tangential shrinkage) is larger by half or more. If a whole log is seasoned before sawing, it will “check” or split open along its length.

7
Q

When are wood distortions most pronounced?

A

When lumber is plainsawn rather than quartersawn.

8
Q

What are five types of seasoning distortions in dimension lumber?

A

Crooking, bowing, twisting, and cupping occur because of nonuniform shrinkage.
Splits (checks) are caused by shrinkage stresses.

9
Q

What is structural grading used for?

A

To rate the strength and stiffness properties of a piece of lumber. Can be done by eye or by machine.

10
Q

How if much structurally graded lumber rated?

A

By species group or species combination.

11
Q

What is appearance grading used for?

A

To rank the visual qualities of lumber intended for flooring, trim, cabinetry, and other finish, nonstructural uses.

12
Q

Light framing lumber must be what appearance grade for floor joists and roof rafters?

A

2 and above

13
Q

Light framing lumber must be what appearance grade for framing?

A

Stud

14
Q

What are the actual dimensions of a nominal 2x4?

A

1.5 x 3.5 inches

15
Q

What are the actual dimension of a nominal 2x6?

A

1.5 x 5.5 inches

16
Q

Lumber in the US is priced by what?

A

The board foot. Based on nominal dimensions, not actual dimensions.

17
Q

What is glue-laminated wood?

A

Small strips of wood glued together to form large structural members, aka glulam. Made for easily controlled size, shape, and quality.

18
Q

How if glue-laminated wood connected within lamination?

A

Finger joints or scarf joints

19
Q

What are cross-laminated timbers (CLTs)?

A

Structural panels laminated from solid lumber, with the orientation of member in each layer alternating from those above and below. Suitable for structural wall, floor, or roof components.

20
Q

What is structural composite lumber (engineered lumber)?

A

Substitutes for solid lumber and are made from wood veneers or wood fiber strands and glue.

21
Q

What is laminated strand lumber (LSL) and oriented strand lumber (OSL) made from?

A

Shredded wood strands, coated with adhesive, pressed into a rectangular cross section, and cured under heat and pressure.

22
Q

What are the weakest, more inexpensive composite lumber products?

A

Laminated and oriented strand lumber.

23
Q

What is Laminated veneer lumber (LVL)?

A

Lumber made from thin wood veneer sheets, as wide as the member is deep, that are glued and laminated into thicker members. It is similar to appearance to plywood but without crossbands.

24
Q

What are three common wood panel products?

A

Plywood, OSB, and MDF

25
Q

What is plywood made of?

A

Thin layers of wood veneer glued together.

26
Q

What is Oriented strand board (OSB) made of?

A

Long shreds (strands) of wood compressed and glued into three to five layers.

27
Q

What material is most commonly used for sheathing and subflooring of light frame wood building?

A

Oriented strand board (OSB)

28
Q

What is medium-density fiberboard (MDF)?

A

Very fine-grained board made of wood fibers and synthetic resin binders. Generally limited to interior uses. Used in the production of cabinets, furniture, moldings, paneling, etc.

29
Q

What are the five veneer grades for softwood plywood?

A

A (highest quality), B, C plugged, C, D (lowest quality)

30
Q

Typical gradestamps for structural wood panels provide what info, from top to bottom?

A

Panel grade, span rating, tongue-and-groove, exposure durability classification, product standard, thickness, mill number, APA’s performance rated panel standard, siding face grade, species group number, HUG/FHA recognition, panel face orientation indicator.

31
Q

Where on a typical gradestamp for structural wood panels can you find the panel grade, span rating, and thickness?

A

The panel grade is at the top (exp. Rated Sheathing). The span rating is below it in bold (exp. 48/24). The thickness is to the right of span rating (exp. 23/32 inch).

32
Q

What are nails?

A

Sharp-pointed metal pins that are driven into wood with a hammer or mechanical gun.

33
Q

What do common nails and box and sinker nails have in common?

A

Flat heads and are used for structural fastening in light frame construction.

34
Q

Finish and casing nails and brads are used for what?

A

They have smaller diameters and heads and are used to fasten finish woodwork.

35
Q

In North America, how are the size of nails measured?

A

In “pennies,” abbreviated “d.”

36
Q

What are ordinary bright nails made of?

A

Plain, uncoated steel

37
Q

What are hot-dip galvanized nails?

A

Corrosion-resistant nails coated in zinc for exterior use.

38
Q

What are the three methods of fastening with nails?

A

Face nailing, end nailing, and toe nailing.

39
Q

What is the actual size of a 16d nail?

A

3.5 inches long, 89 mm diameter

40
Q

What is the actual size of an 8d nail?

A

2.5 inches long, 64 mm diameter

41
Q

What is the strongest nailing method?

A

Face nailing

42
Q

What is end nailing primarily used for?

A

Holding framing members in alignment until gravity forces and applied sheathing make a stronger connection.

43
Q

When is toe nailing used?

A

When access for end nailing is not available.

44
Q

What’s a joist hanger?

A

A sheet metal device for joining wood members or strengthening their joints.

45
Q

Where are joist hangers used?

A

Wherever wood floor and roof framing members bear on one another at right angles. They are attached with special short nails driven through the holes punched in the hangers.

46
Q

What’s the difference between trusses and rafters?

A

Trusses can span further and use less wood than rafters, but they make attic space unusable and ceilings must be flat.