General Requirements of Structural Timber

GENERAL REQUIREMENTS OF STRUCTURAL TIMBER Except as noted, all timber shall be cut from sound trees and sawed standard size; close-grained and solid; free from defects such as injurious ring shakes and crooked grain, unsound knots, knots in groups, decay, large pitch pockets, or other defects that will materially impair its strength.

Standard Size of Sawed Timber -

Rough timbers when sawed to standard size, shall mean that they shall not be over in. scant from actual size specified. For instance, a 12 in. x 12 in. shall measure not less than in. x in.

Standard Dressing of Sawed Timbers -

Standard ing means that not more than in. shall be allowed for dressing each surface. For instance, a 12 in. x 12 in. shall, after dressing four sides, not measure less than in. x in.

Stringers No. 1. Longleaf Yellow Pine and Douglas Fir—Shall show not less than 80 per cent of heart on each of the four sides, measured across the sides anywhere in the length of the piece; loose knots, or knots greater than in. in diameter, will not be permitted at points within 4 inches of the edges of the piece.

No. 2. Longleaf Yellow Pine, Shortleaf Pine, Douglas Fir, and Western Hemlock—Shall be square edged, except it may have 1 in. wane on one corner. Snots must not exceed in their largest diameter the width of the face of the stick in which they occur. Ring shakes extending not over 1/2 of the length of the piece are admissible.

Caps and sills

No. 1. Longleaf Yellow Pine and Douglas Fir—Shall show 85 per cent heart on each of the four sides, measured across the sides anywhere in the length of the piece; to be free from knots over in. in diameter; knots must not be in groups.

No. 2. Longleaf and Shortleaf Yellow Pine, Douglas Fir, and Western Hemlock. Shall be square-edged, except it may have 1 in. wane on one corner, or in. wane on two corners. Knots must not exceed in their largest diameter the width of the face of the stick in which they occur. Ring shakes extending not over 1/2 the length of the piece are admissible.

Posts No. 1. Longleaf Yellow Pine and Douglas Fir. Shall show not less than 75 per cent heart, measured across the face anywhere on the length of the piece; to be free from knots over in. in diameter, and must not be in groups.

NO. 2. Longleaf and Shortleaf Yellow Pine, Douglas Fir, and Western Hemlock. Shall be square-edged, except it may have 1 in. wane on one corner, or in. wane on two corners. Knots must not exceed, in their largest diameter, the width of the face of the stick in which they occur. Ring shakes shall not extend over 1/2 of the length of the piece.

Longitudinal struts or girts

No. 1. Longleaf Yellow Pine and Douglas Fir—Shall show one face all heart; the other face and two sides shall show not less than 85 per cent heart, measured across the face or side anywhere in the piece; to be free from knots in. in diameter and over.

No. 2. Longleaf and Shortleaf Yellow Pine, Douglas Fir, and Western Hemlock—Shall be square-edged and sound; to be free from knots in. in diameter and over.

Longitudinal X-BRACES, SASH BRACES, AND SWAY BRACES No. 1. Longleaf Yellow Pine and Douglas Fir—Shall show not less than 80 per cent heart on two faces and four square edges; to be free from knots over in. in diameter.

No. 2. Longleaf and Shortleaf Yellow Pine, Douglas Fir, and Western Hemlock—Shall be square-edged and sound; to be free from knots in. in diameter and over.