Exam 13: Materials for Wood Construction-I Lumber

Why does a knot present an area of weakness in a lumber member?

What does the term SPF mean? What is the difference between SPF s and SPF? Explain.

A wood member's strength properties are dependent on grain direction. In a wood stud, is the grain aligned vertically or horizontally? In which direction is the grain aligned in a wood beam or joist?

Will two 2 × 8 lumber members nailed together yield one 4 × 8 lumber member? Explain.

Flat- sawn lumber is dimensionally more stable than quarter- sawn lumber.

The walls of wood cells consist primarily of

Explain how fungal decay of lumber can be prevented.

Most lumber used in building construction is visually graded. The traditional visual grading was done by trained graders, who would examine each lumber member for the straightness of grain and the number and size of defects (knots, shakes, and splits)and mark the appropriate grade on the member based on visual assessment. Recently, this procedure has been replaced by an alternative procedure. What is this new procedure called, and what is the fundamental difference between the new and the traditional procedure?

Which of the following grades can only be used as blocking?

Spruce is a softwood species.

Using sketches and notes, explain how to distinguish graphically between framing lumber and finished lumber in cross- sectional drawings.

With the help of a sketch, explain what a termite shield is and where in a building it is typically provided.

Hardwoods are generally used for fine- quality flooring, furniture, and wall paneling.

How can fungal decay of lumber be prevented?

Which of the following lumber cross sections is that of a dimension lumber?

Is it the heartwood or the sapwood (of some wood species)that is recognized as decay resistant? Name these species.

Which of the following grades will not apply to a 2 × 8 lumber?

Which of the following two terms are used synonymously?

After debarking, a log is sawn to required lengths and required cross- sectional sizes. Sawing renders lumber members rough to touch, which can hurt a carpenter's hands. Therefore, the sawn lumber is subsequently surfaced smooth with planing machines. Is surfacing done after the seasoning of lumber or before? Give reason for your answer.

Among the 2- by members, the grades of "Construction," "Standard," and "Utility" are limited to a certain cross- sectional size. Which size is that size?