Wood Trim

Clear Grades

Kiln dried clear grades of western red cedar trim boards graded as finish lumber. Typically available as S4S or S1S2E products.

Grade	Description
	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. Grading Rule Paragraph 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. Grading Rule Paragraph NLGA 200b WCLIB 102-c
	B Clear Permits slightly larger and more numerous characteristics than A grade but occassional pieces may require trimming to yield high grade pieces in shorter lengths. Most often supplied as a percentage with A grade. Grading Rule Paragraph NLGA 200c WCLIB 102-d
	C and Better Clear High quality lumber for use where appearance is important.In addition to interior and exterior trim, lumber of this grade is used for cabinetry, doors, windows and similar applications. Grading Rule Paragraph NLGA 202b, c WCLIB 149-b, c WWPA 10,11, 12
	D Clear This grade permits larger and more numerous natural characteristics and is used where general utility is more important than appearance. Grading Rule Paragraph NLGA 202d WCLIB 149-b, c WWPA 10,13

Knotty Grades

Grade	Description
	Select Knotty Knots are sound and tight. Other characteristics are limited so they do not detract from the end use intended. Typically available commercially as Select allowing 10%-15% Quality Knotty in rough or surfaced products. Grading Rule Paragraph NLGA 204a WCLIB 111-e
	Quality Knotty Natural growth characteristics not limited as stringently as in Select Knotty. Cross cutting may be required on some pieces to yield tight knotted trim boards. Grading Rule Paragraph NLGA 204b WCLIB 111-f
	Proprietary Graded to the manufacturer's specifications to meet the intended end use. Boards often represent good value in the no-hole product range. Consult manufacturers for grade descriptions and nomenclature. Grading Rule Paragraph 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. Typically supplied as S1S2E products. S4S products may require special ordering. Grading Rule Paragraph NLGA 114a,b,c WCLIB 118-a,b,c WWPA 30,50 (118a,b,c)

NLGA - National Lumber Grades Authority
WCLIB - West Coast Lumber Inspection Bureau
WWPA - Western Wood Products Association

Sizes

Thickness (in.)				Width (in.)
Nominal (inches)	Nominal (mm)	Actual (inches)	Actual (mm)	Nominal (inches)	Nominal (mm)	Actual (inches)	Actual (mm)
Rough (Undressed)
1	25	3/4	19	2	51	1-3/4	44
		13/16	21	3	76	2-3/4	70
		7/8	22	4	102	3-3/4	95
5/4	32	1-1/8	29	6	152	5-3/4	146
				8	203	7-3/4	197
				10	254	9-3/4	248
				12	305	11-3/4	298
S1S2E or S4S (Dressed)
1	25	11/16	17	2	51	1-9/16	40
		23/32	18	3	76	2-9/16	65
		3/4	19	4	102	3-9/16	90
		13/16	21	6	152	5-9/16	141
5/4	32	7/8	22	8	203	7-3/8	187
2	51	1-1/32	26	10	254	9-3/8	238
		1-1/2	38	12	305	11-3/8	289
		1-9/16	40

Note:

These are nominal sizes, actual sizes may vary by manufacturer.

Specifications

Specification Information Required	Sample Specification
Species: Western Red Cedar	WRCLA Western Red Cedar
Product Pattern and Intended Use: Trim boards are generally used in applications such as corner boards, fascia, skirting, and detail around windows and doors. Specify the surface finish by choosing surfaced four sides (S4S). surfaced one side and two edges (S1S2E), or rough sawn all round (rough).	S1S2E Boards
Size: Specify the nominal size of the product.	1 x 6 in.
Grade: The grade of the product governs its overall quality. Refer to WRCLA specification literature or grading agency rule books for available grades.	Select Knotty
Grading Agency Paragraph: To ensure that the product meets a written standard, an agency grade paragraph should be referenced.	NLGA paragraph 204a
Moisture Content: Specify whether the product is to be green (unseasoned) or kiln-dried.	Green
Surface to be exposed: Specify the application orientation to assist the supplier in shipping the right product for the job.	Resawn face
Quantity: Express in linear feet	2000 linear feet

Textures

Western Red Cedar boards may be specified in one of three surface finishes: rough; surfaced one side, two edges (S1S2E); or surfaced four sides (S4S).

	Rough Boards The rough sawn texture from either circular or band saws is present on all four sides.
	Surfaced One Side, Two Edges (S1S2E) This versatile product is the most popular choice for trim boards. The surfacing process resulting in a rough sawn face and a smooth back provides uniform width and thickness tolerances. Typically graded from the rough face, it may in some instances be reversible to the smooth back.
	Surfaced Four Sides (S4S or PAR, D4S) The smooth surface on all four sides presents a uniformly sized product with a quality appearance. This surface finish is most commonly found on Clear grades.

Fasteners

Surfaced One Side, Two Edges (S1S2E)

Hot-dipped galvanized, aluminum and stainless steel fasteners are all corrosion-resistant and can be used to fasten Western Red Cedar. Other types of nails are not recommended. They can rust and disintegrate and react adversely with the natural preservative oils present in cedar resulting in unsightly stains and streaks. Copper nails also react with cedar and should not be used. Stainless steel nails are the best choice, especially if trim boards are to be finished with transparent or semi-transparent stain. Use No. 304 stainless for general applications and No. 316 for seacoast exposures.

For best results use splitless fasteners designed for siding installation. This type of nail has a thin shank and blunt point and is available with a ring or spiral shank. Fastener length should be adequate to provide a minimum penetration of 1½" (38mm) into solid wood.

Finishing

Although Western Red Cedar trim boards are naturally durable, a finish is strongly recommended to ensure a long, trouble-free service life. Information about finishing can be found in the WRCLA publication Guide to Finishing Western Red Cedar (800K pdf)

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