How to be a pressure treated lumber expert

By Karl Lindberg Vice President Southern Forest Products Association

ir REATED lumber is one of the l "hottest" products in reail building materials today. In the south, CCA preservative-Pressure treated southern pine accounts for morethan one-third of all production. Some analysts predict it will increase to 5090 by 1990.

Pressure treated lumber increases your store trafFrc because it has made consumers more conscious of outdoor living projects. In addition to the lumber itself, pressure treated southern pine offers unique add-on sales opportunities through extra volume in power tools, hand tools, hangars, nails, hardware, Paint and stains. Many dealers offer a contracting service to design and install outdoor decks and fencing for their customers.

The three wood sPecies which are best suited for pressure treating are southern pine, Ponderosa Pine, and red pine. Southern pine is widely regarded as the most "treatable" species because of its cellular struclure which permits deep, uniform penetration of the CCA preservative treatment.

Fir, hemlock, and other sPecies usually need to be incised before the chemicals will penetrate the wood under pressure. Incising is a series of slits along the grain of the wood which assist chemical penetration.

Treated southem pine is an economical substitute for durable species such as cedar and redwood, which may be in short supply in the future.

Nobody knows exactly how long pressure treated southern pine will last. In government sponsored exposure tests, 2 x 4 stakes buried in the soil in the 1930s are still in sound condition.

Several manufacturers guarantee their pressure treated lumber for decades. These warranties are possible because the CCA preservatives forced into the wood under Pressure form a chemical bond within the wood cells.

Just because treated lumber has a green color, it may not meet the durability and end use requiremerts which your customers require. Since all treated lumber is not the same quality, retailers need to know which products me€t industry quality *andards.

Pressure treated lumber should be stamped to indicate the retention level, which measures the amount of chemical treatment per cubic foot of wood. The higher the retention number, the more severe exposure conditions the wood can stand.

The various retention levels are intended for specific end uses. These are the designations you will see on the stamp: for two stamps. The fint is the grademark which relates to the $ructural quality of the lumber. (Such zts Southern Pine Inspection Bureau or Timber Products Inspection.) The second is the treated stamP of the quality control agency. It indicates which agency inspected the lumber after treating, what retention level the treated lumber received, and what kind of preservative was used.

Most of the 3 billion board feet of pressure treated southern pine produced annudly goes into outdoor sundecks, fencing, Yard structures, planters, permanent wood foundations, bridge timbers, and other industrial and farm uses.

To get the most from Pressure treatd lumber, remember that:

(l) treated lumber should have covered storage at your retail yard or home center.

(2) treated wood scraPs should be discarded in the trash instead of being burned.

(3) clothes which have accumulated sawdust from treated lumber should be laundered before reus€, and washed separately from other clothing.

(4) when sawing or machining treated lumber (or untreated lumber), eye goggles and a dust mask should be worn.

(5) you should use hotdiPPed galvanized or stainless seel nails and fasteners with treatd lumber-not aluminum or carbon steel nails.

The treating industry follows a three-level system of quality control. One level is the American Wood Preservers Bureau, the national overview agency, which certifies a number of quality control agencies. These agencies form the second level of the industry, monitoring and testing quality control standards at the individual treating plants. The third level is the in-plant quality control maintained by each treating company.

When examining a piece of pressure treated lumber, you should look

(6) you should predrill holes or dull the sharp points of your nails to reduce the possibility of splitting the lumber when nailing near the ends.

(7) a coat of water repellent sealer should be applied to the treated lumber after it is in place on a construction project. This will improve the appearance and durability. After you brush on a coat of water repellent, you can let the lumber weather to an attractive gray color. Or, you can let it searcn for a few weeks and apply a coat of Paint or stain.

In summary, pressure treated southern pine lumber will increase your sales and profitability today and in the future, if you purchase quality products which meet your customer's needs.

For a fre copy of SFPA's new Outdoor ldea Book, and additional information on trealed lumber, write Southern Forest Products Association, Box 52468, New Orleans, La' 70152. -ed.