| |
Rating |
Description |
|
Availability |
A
B
C
D
E |
Readily available
Generally available
Limited availability
Only small quantities available
Very limited supply |
|
Suitability for use |
F
G
H
I
J |
Suitable heart or treated
Suitable treated
Suitable untreated
Suitable heart
Not suitable, or not usually used |
|
Grades suitable for building |
K
L
M
N |
No 1F and No 2F
Framing
No 1 and No 2 grading rules, unassigned strengths
No grading rules, and no assigned strength |
|
Grading suitable for engineering uses |
O
P
Q
R |
Grading rules and strengths
Grading rules, and no assigned strength
No grading rules, but assigned strengths
No grading rules, and no assigned strength |
|
Natural Durability of heartwood |
S
T
U
V |
Perishable (5 years)
Non-durable (5-10 years)
Moderately durable (10-15 years)
Durable (15-20 years) |
