SPECIFYING CEDAR SIDING - Real Cedar

KNOTTY GRADES OF WESTERN RED CEDAR BOARD-AND-BATTEN SIDING
Grade Description Grading Rule Paragraph 1
Select Knotty*
Quality Knotty
Proprietary**
Standard and Better***
21
Knots are sound and tight. Other NLGA 204a
characteristics are limited so they WCLIB 111-e
do not detract from the end WWPA N/A
use intended.
*Typically available commercially as
Select allowing 10%–15% Quality Knotty
in rough or surfaced products.
Natural growth characteristics not NLGA 204b
limited as stringently as in Select WCLIB 111-f
Knotty. Cross cutting may be WWPA N/A
required on some pieces to yield
tight knotted siding.
Graded to the manufacturer’s NLGA N/A
specifications to meet the intended WCLIB N/A
end use. Boards often represent WWPA N/A
good value in the no-hole
product range.
**Consult manufacturers for grade
descriptions and nomenclature.
Suitable for exterior construction. NLGA 114a, b, c
Occasional pieces may require WCLIB 118-a, b, c
trimming to yield suitable quality WWPA 30.50 (118a, b, c)
for the intended end use.
*** Typically supplied as S1S2E products.
S4S products may require special ordering.
1 NLGA – National Lumber Grades Authority
WCLIB – West Coat Lumber inspection Bureau
WWPA – Western Wood Products Association