Standard Sizing

Southern Pine

Lumber Sizing

Securing and using properly sized Southern Pine lumber is crucial for a successful and longstanding project. The right-sized lumber can ensure structural integrity, safety, and efficiency, which is why it’s important to understand standard sizing for dimension, board, and finish lumber dressed, in addition to radius edge decking.

Achieving optimal results with Southern Pine lumber sizing requires a holistic approach that includes:

Other factors include load-bearing requirements and span distances to ensure the structural elements of your project – such as beams, joists, and studs – can adequately support the loads for which they are designed.

Choosing the right lumber size can also minimize waste, reduce the need for additional cutting and shaping, and optimizes material usage.

If you’re unsure about the size or type of lumber to use for your project, contact a professional builder or architect who can provide guidance based on your specific needs and local regulations.

The Southern Forest Products Association provides standard sizing for the following lumber below:

Dimension Lumber dressed, S4S1

Thickness					Width
Nominal	Dressed				Nominal	Dressed
	Dry		Green			Dry		Green
inches	inches	mm	inches	mm	inches	inches	mm	inches	mm
2	1-1/2	38			2	1-1/2	38
2-1/2	2	51	2-1/16	52	3	2-1/2	64	2-9/16	65
3	2-1/2	64	2-9/16	65	4	3-1/2	89	3-9/16	90
3-1/2	3	76	3-1/16	78	5	4-1/2	114	4-5/8	117
4	3-1/2	89	3-9/16	90	6	5-1/2	140	5-5/8	143
					8	7-1/4	184	7-1/2	190
					10	9-1/4	235	9-1/2	241
					12	11-1/4	286	11-1/2	292
					14	13-1/4	337	13-1/2	343
					16	15-1/4	387	15-1/2	394
					18	17-1/4	438	17-1/2	444
					20	19-1/4	489	19-1/2	495
Timbers dressed, S4S¹	Timbers dressed, S4S¹		Timbers dressed, S4S¹		Timbers dressed, S4S¹	Timbers dressed, S4S¹		Timbers dressed, S4S¹
5" & thicker	1/2' off nominal		1/2' off nominal		5" & thicker	1/2' off nominal		1/2' off nominal

Boards dressed, S4S, dry

Thickness			Width
Nominal	Dressed		Nominal	Dressed
inches	inches	mm	inches	inches	mm
1	3/4	19	2	1-1/2	38
1-1/4	1	25	3	2-1/2	64
1-1/2	1-1/4	32	4	3-1/2	89
			5	4-1/2	114
			6	5-1/2	140
			7	6-1/2	165
			8	7-1/4	184
			9	8-1/4	210
			10	9-1/4	235
			11	10-1/4	260
			12	11-1/4	286
			over 12	3/4" off nominal	19 mm off nominal

Finish dressed, dry

Thickness			Width
Nominal	Dressed		Nominal	Dressed
inches	inches	mm	inches	inches	mm
3/8	5/16	8	2	1-1/2	38
1/2	7/16	11	3	2-1/2	64
5/8	9/16	14	4	3-1/2	89
3/4	5/8	16	5	4-1/2	114
1	3/4	19	6	5-1/2	140
1-1/4	1	25	7	6-1/2	165
1-1/2	1-1/4	32	8	7-1/4	184
1-3/4	1-3/8	35	9	8-1/4	210
2	1-1/2	38	10	9-1/4	235
2-1/2	2	51	11	10-1/4	260
3	2-1/2	64	12	11-1/4	286
3-1/2	3	76	14	13-1/4	337
4	3-1/2	89	16	15-1/4	387

Radius Edge Decking dressed, S4S, dry

Thickness			Width
Nominal	Dressed		Nominal	Dressed
inches	inches	mm	inches	inches	mm
1-1/14	1	25	4	3-1/2	89
			5	4-1/2	114
			6	5-1/2	140

Disclaimer:

These easy-to-use tables were compiled by the Southern Forest Products Association (SFPA) as a service to design/build professionals and other Southern Pine users.

Reference design values are for normal load duration under the moisture service conditions specified. SFPA does not grade or test lumber, and accordingly, does not assign design values to Southern Pine lumber. The design values contained herein are based on the Southern Pine Inspection Bureau’s Standard Grading Rules for Southern Pine Lumber and modified as required by the American Wood Council’s National Design Specification® (NDS®) for Wood Construction. Accordingly, neither SFPA, nor its members, warrant that the design values on which the span tables for Southern Pine lumber contained herein are based are correct, and specifically disclaim any liability for injury or damage resulting from the use of such span tables.

The conditions under which lumber is used in construction may vary widely, as does the quality of workmanship. Neither SFPA, nor its members, have knowledge of the quality of materials, workmanship or construction methods used on any construction project and, accordingly, do not warrant the technical data, design or performance of the lumber in completed structures.