The largest expense in a truss plant’s operation is the lumber cost. It often represents 50% to 60% of the selling cost of the truss. With such a high percentage, most managers are always focused on saving lumber, optimizing lumber, and searching for the best price. Those aspects are vital, but are you also keeping an eye on how your lumber is received? Are you maximizing the value of the product where you have invested so much?
Lumber receiving starts with selecting the best choice for your supply of lumber. Proper seasoning, milling, grading, and processing is the most important first step. Properly seasoned lumber provides optimal dimensional stability and helps improve its suitability and permanence once the lumber is in service. To minimize shrinkage, grading rules for Southern Pine requires lumber less than 2” to be kiln-dried or seasoned to a moisture content not to exceed 19%. This will result in an average moisture content of about 15% at the time of manufacture. Once the lumber is at the plant and then in service, it will adjust to the moisture content of its end use environment.
Here are a few recommendations to keep your lumber in its best condition, improving its value once it arrives on your customer’s building site.
- Keep proper records of receiving lumber. Have a checklist that is reviewed and recorded as the lumber is received.
- Conduct a sampling to verify content and grades. Learn and understand stamps so you can verify proper grade-marking and moisture content.
- Verify the lumber has been dried per your purchase order. Some plants do this with a moisture probe.
- If banding is removed, make sure banding is replaced for intermediate storage to help prevent distortion of the lumber due to environment.
- Inspect for mold and other conditions that would require attention. Learn to identify the dangers of mold and the dangers of certain types of mold.
- Because often lumber loads are not wrapped or tarped, consider adding this requirement to your purchase order. It won’t guarantee dry, but it won’t hurt, especially if your plant stores lumber in the dry.
- Unload lumber in a dry place. Do not place in wet or muddy areas.
- Elevate lumber on stringers to prevent absorption of ground moisture and to allow air circulation.
- Keep the lumber shaded or out of the direct sun.
- Do not store lumber in direct contact with the ground.
- Cover lumber stored in an open area with a material that will give protection from the elements. Polyethylene or similar non-porous materials act as a vapor barrier, so it is important to allow ventilation around the material to prevent condensation on the underside of the covering.
- When possible, store lumber under enclosed or under roof as soon as possible.
- Know the limits of paper wrapping. Some mills offer protection by providing paper-wrapped packaging that has been treated with a weather protective coating. However, this service can be limited, and weather-protective coatings are generally effective for only about three to six months. Damage to the paper during transportation can reduce its effectiveness, and protection is lost when paper wrappings are removed.
Remember, a great truss product begins with great material!
An ANSI/TPI 1 3rd Party Quality Assurance Authorized Agent covering the Southeastern United States, Glenn Traylor is an independent consultant with almost four decades of experience in the structural building components industry. Glenn serves as a trainer-evaluator-auditor covering sales, design, PM, QA, customer service, and production elements of the truss industry. He also provides project management specifically pertaining to structural building components, including on-site inspections and ANSI/TPI 1 compliance assessments. Glenn provides new plant and retrofit designs, equipment evaluations, ROI, capacity analysis, and CPM analysis.