Engineered wood beams made understandable

By Bill Rooney

a\ OMPARED to wide dimension

V solid lumber, the new engineered wood beams are straighter and stronger, lighter and longer. No contractor argues these benefits. They also appreciate what they don't get with these products - bouncing, squeaking floors or telltale cracks in the ceilings.

Today, the market for engineered beams is a lot more than just window, door and garage door headers. Industry experts estimate that 5-70/o of new homes built use engineered floor or roofbeams. By 1995, figures are expected to reach 15-200/o and by the turn of the century, the number will be more like 30-40V0 of the homes.

Some of your professional customers, contractors, builders and remodelers. are now using one or several of these products on their

Story at a Glance

Benefits and advantages of engineercd wood beams... guide to selecting those your customers want tipson productcomparison.

jobs. And don't overlook your remodeler customer since these beam benefits are equally important to his customers.

Not too long ago, selecting an engineered wood beam supplier was a fairly simple task. Either you worked with a regional glulam manufacturer, selected one ofthe few I-beam products or perhaps supplied both items on special request. Well, life is no longer simple. Today many of the major forest products companies are competing directly with the established independent producers. A variety of beam styles, engineering performances, accessories and technical back-up are available to the retail dealer. How do you start narrowing your choices?

Glulam beams, which have been around for 30 years or more, now feature three grades manufactured from kiln dried, machine stress rated lumber in exterior and interior products with fire ratings. Various wood species are used to produce straight, curved, arched and special shapes for all structures from churches and warehouses to dome homes and bridge members.

I-beams have come a long way from the early pioneering efforts of Trus Joist. The l-beam of today is becoming a workhorse commodity product, available from local inventory. The web or vertical section may be plywood or OSB in single or double construction in a variety of thicknesses. Flange material can be stress rated finger jointed lumber, or ply- wood or laminated veneer lumber members.

LVL beams are a lot more than just fat plywood. Waterproof adhesive bonds Douglas fir or southern pine veneers with the grain running parallel in all plies. Unlike plywood, the LVL veneers are densified, that is, the thickness is compressed to where l5-20 veneers make up the typical l-3l4-inch thick billet.

PSL, parallel strand lumber, the patented process developed by Canadian giant MacMillan Bloedel over the past 20 years, starts with dried and graded l/8-inch thick softwood veneer. The veneer is sliced into 8foot long strands, approximately | /2inch wide, coated with adhesive and the parallel-oriented strands are fed into a huge press. The randomly overlapped strands are progressively squeezed into a finished 12x18-inch billet 60-feet long and cooked with 400,000 watts of microwave energy to instantly cure the adhesive.

Composite lumber beams, as exemplified by the Arrowood product from Fibreboard Technologies, combine top and bottom LVL flanges in a vertical arrangement with a thick OSB web to produce a solid slab beam l-l/2-inches thick by 36-feet long in a range of depths.

So how do you evaluate which beam or beams you should be supplying?

( 1 ) Conduct some local horSeback research. Talk with your contractors and builders about what they are using for beams and who is specifying the product. Then contact those architects and engineers to determine what they specify, and more important, what they would like to use on future jobs. ments? Special orders? And how well do you and the local salesperson work together? Yes, and then ask about pricing. But with beams, performance or product and supplier come long belore the pricing question.

(21

Tech.nical evaluation of beaRrs slarts with a comparison of the engineering numbers. Stiffness, called "deflection," relates directly to strength and is measured by MOE, modulus of elasticity. Bending stress and shear strength, or the beam's ability to resist breaking in two, are additional important numbers. How broad is the beam manufacturer's product line? Exterior as well as interior grades? Clean, appearance grades as well as industrial grades? Can he supply fire retardant and/or preservative treated beams? Unlike most beams, glulams and parallel strand lumber beams are available as posts and columns as well as horizontal members. ls this important in your market?

(3) Finally. research those critical hon-product questions of each supplier. What kind of engineering back-up support can you expect to eliminate or at least minimize your potential product liability? What type of product and sales training is offered for your staff? Is regional inventory support available? What about quick ship-

With all the established players plus the rush of new major beam producers, the industry is looking at more capacity than customers. During the next few years, even as the beam market expands and matures, there will be a series of mergers and acquisitions. Select your beam suppliers carefully so you don't get caught in the coming industry shakeout.

After you have done your local research and asked all the right questions, verify your decision with one additional contact. Talk with your Simpson Strong-Tie representative or someone from a similar metal connector company. Since they work directly with most of the various beam manufacturers, they should be in a knowledgeable position to confirm your decision.

Unquestionably, the engineered wood beam market will expand dramatically in the next decade. Get in on the ground floor now. Because the ground floor will be built with glulams, or l-beams or LVL's or PSL's or composite beams.