Light Framing

Construction
Douglas Fir

In Construction grade pieces are of good appearance but graded primarily for strength and serviceability. Sound, firm, encased knots are tight and limited to no larger than 38 mm. Unsound or loose knots or holes are limited up to 25 mm, one per 910 mm. Maximum allowable wane up to 1/4 the thickness and 1/2 the width full length, or equivalent on each face, provided that wane not exceed 1/2 the thickness or 1/3 the width for up to 1/4 the length. 

Standard
Douglas Fir

This grade is customarily used for the same purposes or in conjunction with Construction grade. Characteristics are limited to provide good strength and excellent serviceability. Knots are not restricted as to quality up to 51 mm anywhere in the wide face. Holes are limited up to 32 mm, one per 610 mm. Limitations on wane apply.

Stud
Douglas Fir

Intended for vertical installations in load-bearing applications. Knots are not restricted as to quality but must be well spaced and limited up to 38 mm, one per 310 mm. Limitations on crook, splits, shake, and edge knots. Wane, as in pieces #3 and #4, is allowed up to 1/3 the thickness and 1/2 the width full length, or equivalent on each face, provided that wane not exceed 1/2 the thickness and 3/4 the width for up to 1/4 the length.

Construction
Hem-Fir

Recommended and widely used for general construction purposes. Pieces are of good appearance but graded primarily for strength and serviceability. Sound, firm, encased knots are tight and limited to no larger than 38 mm. Unsound or loose knots or holes are limited up to 25 mm, one per 910 mm. 

Standard
Hem-Fir

This grade is customarily used for the same purposes or in conjunction with Construction grade. Characteristics are limited to provide good strength and excellent serviceability. Knots are not restricted as to quality up to 51 mm anywhere in the wide face. Holes are limited up to 32 mm, one per 610 mm. Piece #5 includes white speck.

Stud
Hem-Fir

Used for vertical installations, such as wall framing. May be manufactured to the full basic length and double-end trimmed or may be precision-end trimmed to exact lengths. Knots are not restricted as to quality but must be well spaced limited up to 38 mm, one per 310 mm. Limitations on crook, splits, shake, and edge knots. Allowable wane shown in pieces #1 and #4.