Frequently Asked Questions

Here are answers to some of the more frequently asked questions about Southern Pine. If you
don't find an answer to your question on our site or in these FAQs, please contact our Wood
Products Help Desk.

• About the Southern Pine species
• General lumber questions
• Pressure-treated lumber questions
• Material Handling and Phytosanitary Compliance
• Outdoor deck tips and other yard projects
• Porch flooring tips and projects
• Southern Pine interior flooring
• Environmental
• Miscellaneous

Material Handling and Phytosanitary Compliance

• Is Southern Pine suitable for my global material handling needs?
  Yes. Southern Pine lumber is kiln dried. Southern Pine's natural assets – high strength, fastener holding ability and wear resistance – are further embellished in the manufacturing process. Most Southern Pine lumber produced, about 95%, is kiln dried. The kiln-drying process further increases strength and nail holding power, improves stability, results in uniform sizes, and meets the core temperature requirements of international phytosanitary rules.
  Top
•  
• How does Southern Pine kiln drying compare to minimum HT requirements?
  The core temperature of kiln-dried Southern Pine exceeds HT phytosanitary requirements. Typically, kiln schedules for drying Southern Pine exceed 12 hours at 200º Fahrenheit – often higher – thereby far exceeding the core temperature requirement of 56º Centigrade (133º F) for 30 minutes set by the international phytosanitary rules for non-manufactured wood packing material.
  Top
•  
• Does Southern Pine meet moisture limits set by the phytosanitary rules?
  The phytosanitary rules require that wood for packaging contain less than 20% moisture content at the time of manufacture. To be grade marked, Southern Pine lumber must be kiln dried to a moisture content of 19% or less.
  Top
•  
• What is the standard for heat treatment of Southern Pine lumber?
  The Southern Pine Inspection Bureau (SPIB) sets quality standards for Southern Pine manufacturing and grade marking. SPIB defines lumber as being heat treated when "placed in a closed chamber with artificial heat until the lumber achieves a minimum core temperature of 56 degrees Centigrade for a minimum of 30 minutes. The lumber must be in the green condition at the time of heat treatment."
  Top
•  
• What about pressure treatment for phytosanitary use?
  Pressure-treated lumber is infused with preservatives to resist insect damage and decay. Although the process results in pest-free lumber, pressure treatment alone will not suffice for the phytosanitary rules. According to regulation, the lumber first must be kiln dried prior to pressure treatment, a standard procedure for HT compliant Southern Pine. Kiln-dried Southern Pine is a preferred wood for pressure treatment because of its ability to achieve deep, uniform penetration of wood preservatives. Pressure treated Southern Pine is also available re-dried, Kiln Dried After Treatment (KDAT).
  Top
•  
• Do phytosanitary rules affect other wood products that I use?
  Rules adopted under the United Nation's International Plant Protection Convention require heat treatment of all non-manufactured (solid sawn) softwoods and hardwoods used in packaging destined for export. By the nature of their production process, manufactured wood products such as plywood, oriented strand board (OSB) and laminated veneer lumber are exempt from the phytosanitary restrictions and are not required to bear an ''HT'' mark. However, packaging units made of both non-manufactured and manufactured wood components must still bear an ''HT'' audit mark.
  Top
•  
• Where can I find sources of supply for heat-treated lumber?
  Visit the Product Locator and select the Material Handling category.
  Top

Outdoor deck tips and other yard projects

• What is the maximum span of Southern Pine radius edge decking?
  The maximum recommended span for 5/4 Radius Edge Decking (R.E.D.) or Patio Decking manufactured from U.S. grown Southern Pine is 24 inches on center installed perpendicular to the joists. Be aware the maximum recommended span for 5/4 R.E.D. manufactured from imported Southern Pine (stamped I-SP) or Caribbean Pine (I-CARIB) is only 16 inches on center. For more information, visit www.SouthernPineDecks.com.
  Top
•  
• Does my new deck need staining or sealing?
  See Finishing & Maintenance tips at www.SouthernPineDecks.com.
  Top
•  
• How can I minimize warp and cracks in my deck?
  See Real Wood Decking and Finishing & Maintenance tips at www.SouthernPineDecks.com.
  Top

Porch flooring tips and projects

• Where can I find kiln dried (KDAT) Southern Pine porch flooring?
  For best results, Southern Pine porch flooring should be pressure treated and then kiln dried after treatment (KDAT). It is a popular product so many local dealers carry it. See our Product Locator. Also for more information, see Building a Porch at www.SouthernPineDecks.com.
  Top
•  
• What is the maximum span for Southern Pine porch flooring?
  The maximum recommended joist spacing for installing Southern Pine tongue & groove porch flooring is 16 inches on center. See Building a Porch at www.SouthernPineDecks.com.
  Top
•  
• Should porch flooring be pressure treated?
  To combat the deteriorating effects of outdoor exposure, moisture, decay and termite attack, pressure treatment with a waterborne preservative is recommended for all wood components of a porch. See Building a Porch at www.SouthernPineDecks.com.
  Top
•  
• Can I convert a concrete porch to comfortable wood?
  The member magazine of the Handyman Club of America, HANDY, offers a plan for converting a concrete porch to a comfortable, charming wood porch without the labor of removing the concrete. Download the project from the Building a Porch at www.SouthernPineDecks.com.
  Top