These guidelines are intended to assist in specifying the most economical and efficient use of Southern Pine lumber products. They should also help minimize misunderstandings between specifier and supplier. Product availability and economy varies by market area. Becoming familiar with the products available in your area will allow you to more easily obtain materials to satisfy your demands.
Identification and Quality Control - Each piece of lumber should be grademarked by an agency accredited by the American Lumber Standard Committee (ALSC), and manufactured in accordance with Product Standard PS 20 published by the U.S. Department of Commerce. View typical Southern Pine grade marks by clicking here.
Product Classification - Products should be identified by manufactured categories such as Dimension, Structural Light Framing, Decking, Boards, Timbers, etc. Products in categories such as Finish, Flooring, Ceiling, and Siding, etc., should include the pattern name and number assigned by the ruleswriting agency. This will correctly identify the product and ensure that it conforms to standard. Select from the grade descriptions here.
Size and Length of Pieces - Products included in lumber standards, such as Dimension Lumber, should be specified by nominal sizes for thickness and width, and by common lengths which are 8' to 20' in two-foot increments. Products with patterns and special orders should include the desired net, dry size, plus the dimensioned profile pattern for less common items. View standard sizes by clicking here.
Grade and Strength of Material - Standard grades for each product class should be specified after considering all grades appropriate for the intended use and strength requirements. For structural applications, include the required design values along with the grade that represents those design values.
Moisture Content - Specify desired moisture content (percent) based on requirements for the product, grade and intended use. Most product classes and grades of Southern Pine have specific moisture requirements. View moisture content limits by clicking here.
Surface Texture - Surfacing requirements should be specified. Lumber is commonly ordered S4S (smooth surfaced on all four sides), or rough sawn. Other examples include: S1S2E (surfaced one side and two edges); or S2S&CM (surfaced two sides and center matched on edges with centered tongue and groove). Variances from S4S will cause a change from the standard dressed sizes, so the effect on desired net dry size should be considered. Refer to the SPIB Standard Grading Rules for Southern Pine Lumber for more information on surfacing designations and net product sizes.
Transportation and Storage - All lumber in transit, storage and handling areas should be protected from moisture, weather and contaminants. Coatings, wrappings or coverings should allow circulation and not trap moisture. View proper storage guidelines by clicking here.
Preservative Treatment - When pressure-treated lumber is required, it should be treated according to appropriate American Wood-Preservers' Association (AWPA) Standards. Quality control for treating should be done by an approved inspection agency. Each piece of lumber should be identified with a quality mark or end tag bearing the name of the inspection agency, applicable AWPA Standard, use exposure, preservative used, retention level, treating company and year of treatment. Jobsite fabrication cuts and borings should be field treated with copper naphthenate having a minimum 2% metallic solution in accordance with AWPA Standard M4. Products preservatives, uses and standards are described at Pressure-Treated Southern Pine.
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