Siding Types - Tongue &
Groove - Grades Grades of Western Red Cedar
Pattern Siding
Grade
Description
Grading Rule Paragraph
CLEAR GRADES
Clear Heart
The highest grade. Includes only pieces with
heartwood on the exposed face. Many pieces completely
clear, others have minor imperfections that do
not detract from their fine appearance.
NLGA 200a
WCLIB 102-b
A Clear*
Permits somewhat more imperfections than Clear
Heart but the grade is still restricted to pieces
with excellent appearance.
*Common specifications are A and Better and
A and Better with a percentage of B grade allowed.
NLGA 200b
WCLIB 102-c
B Clear
Permits slightly larger and more numerous characteristics
than A grade and occasional pieces may require
trimming to yield high grade pieces in shorter
lengths. Most often supplied as a percentage with
A grade.
NLGA 200c
WCLIB 102-d
KNOTTY GRADES
Select Knotty
Available kiln dried or unseasoned. Knots are
sound and tight.
NLGA 204a
WCLIB 111-e
Quality Knotty
In this grade, natural growth characteristics
are not limited as stringently as in Select Knotty.
Cross cutting may be required on some pieces to
yield tight knotted siding.
NLGA 204b
WCLIB 111-f
Proprietary Grades
Designed to meet appearance requirements for
cedar sidings and trim. Ask your WRCLA distributor
for details.
*Manufacturers may market their own proprietary
grades.
NLGA n/a
WCLIB n/a
Standard and Better
Suitable for exterior construction. Occasional
pieces may require trimming to yield suitable
quality for the intended end use.
1NLGA - National Lumber Grades Authority
WCLIB - West Coast Lumber Inspection Bureau
