Shaving off 1132" can save trees for years to come

lfOW do you answer a cuslomer's Ilcomplaint that a 1/2 inch thick structural wood panel measures only 1582 of an inch?

"When it comes to performance, ll32 of. an inch is virtually meaning- than halfof 1990 sales and only 52Vo of the trget established by Congress. Sales in Washingon and Oregon were only 23% of the targeted figure; Southwestern Region, 4O7o; Pacifrc Southwest region, 46%; Northern regSon,54%. less, but as a means of getting the most out of the tinber resource, lB2 of an inch can help ensure a continued supply of timber for years to come," is the answer recommended by the American Plywmd Association.

Policies for Structural-Use Panels, has been applied to 15132, 19132 and 23132 inch thick panels since 1980. This allows flexibility in manufacuring yet assures panels meet the demands of the job they're designed for, regardless of thiclness. In developing the performance standards, APA engineers and wood scientists discovered that in most cases, 15/32,19132 md 23F,2 inch panels marched the performance required of traditional l12, 5/8 and 3/4 inch panels respectively.

"The p'roblem is only going o get worse unless the Clinon administs'ation takes immediate action," warns APA president David L. Rogoway.

Structural wood panel demand continues to grow. APA expecs a 4% ncreax, this year and 3.5% next year, reaching 29.5 bllion squae feet in 1994. Total U.S. strucural panel mill operating capacity as measured by equipment capacity is 30.5 billion squarc feet, but some 3 b,illion feet of capacity has been closed in the West since 1990 due primarily oo lack of adequate log and veneer supplies. An additional 1.6 bitlion feet of equipment is idle in l0 westem and inland region mills because of resource shortages and another 6(X) millien fsel of capacity could be lost in the West this yea if timb€r htrvest constraints arc not moderated.

Al5l32 inch thick structural wod panel contains 6Vo less wood fiber than a ll2 inch thick panel. When you multiply 64o by millions of panels, you end up conserving not just wood fiber, but whole trees.

The American Plywood Association's quality auditing and testing ensures adequate performance. APA PRP-108, Perfonnance Standards and

Span rating, not thickness, is the best indicaor of srength and stiffness when determining the right panel. It denotes the maximunr recommended cent€r-to-c€nter spacing in inches of supports over which the panel should be installed. The left hand number is the maximum recommended center to center spacing of supports for roof sheathing, the right hand number for subflooring. Both assume the panel will be installed with the long dimension perpendicular to supports.

Conserving the tinber resource is vial as structural wood panel demand grows and federal timber sales and hanvests shrink due to preservationist lawsuits and injunctions, APA explains. Harvests of timber administered by the U.S. Forest Service fell l47o nattonally last year, down 307o from 1990. Forest Service timber sales in fiscal year 1992 were less

Western production declined for the fifth consecutive year in 1992 at 4.9 billion square feet (3/8 inch basis), down nerly 4% ftom l99l md 467o from 1987. Althougb nationwide production ro*,1Vo, other regions are finding it increasingly difficult to make up Oe western region shatfall, Rogoway points ont

"The price increases we've seen recently for wood p'rofucS is the predictable outcome of growing deinand in the face of artificially constrained resourc€ supplieg" be said"

Production declines also affected sanded plywood which was down l0% in 1992, a 500 million square feet shorfall, desptb a 13% ins€ase in the South.

So, when the customer asks, point otrt ll32 of an inch can make a lot of difference in supply and price.

Story at a Glance

What to say when customers question thickness of structural wood panel 15192" thick uses 696 less wood fiber than 1f2" wlth guaranteed performance and conserves timber supply.