Gruen-Wald Engineered Laminates was created by a Structural Engineer named Duane Boice, to fill a need felt by post frame builders and suppliers nearly a decade ago!
“The new hybrid lumber is unstable and can’t be used in buildings like the old growth timber could”, lamented post frame suppliers to Structural Engineer, Duane Boice. Since Duane had never understood the word “can’t”, he began an extensive research project to determine “how to make crooked wood go straight”. He studied the process of laminating various plies of wood and determined that the solution was to cut large timbers into layers and then, after re-orienting the adjacent plies so that the grain no longer matched, laminate the several plies together. One potential method was a wire tie machine that pulls thin stainless steel wires through the boards and leaves them embedded, connecting the plies. Simple calculations revealed that the wire tie, at best, could only hold Southern Yellow Pine together until the moisture content changed 3%, then the plies would begin to pull apart. Ring shank nails were also considered since they hold more than the wires, however, to equal the glu-laminated column holding power, one 20d ring shank nail would need to be placed every square inch of the column surface, literally destroying the integrity of the wood plies.
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to be the best, needed to use the best glue with the longest track record available. Borden Chemical’s phenolresorcinol two part permanent adhesive was chosen because it absorbs into the interstitial pores of the adjacent plies and then chemically “locks” the two together in a permanent bond. It is not water soluble and is totally inert once set. The glu-line appears to be less than a hair thick, but really encompasses part of each adjacent ply.
Gruen-Wald Engineered Laminates, tried to reduce the cost of manufacturing by treating the glu-lam columns after being glued. However, this process created more problems than it solved. For one thing, the columns were heavy. They had to “drip dry” over a long period of time and they required hot dipped galvanized nails be used to attach girts and trusses. (Electroplate galvanized nails will be eaten up by the treating materials within 5 to 7 years.) Numerous columns were cut and cored to check treating levels and only about ¾” of the exterior faces were adequately treated. This showed a need to use treated 2x materials to make the treated portion of the columns.
Now, the question was, “what treating penetration level is required”? Research revealed that
.40 CCA retention was not adequate while the
.80 CCA retention lumber suffered some in allowable strength.
.60 CCA treated Southern Yellow Pine was chosen because it treats more thoroughly than any other species and is much more stable than the cheaper Ponderosa Pine. Gruen-Wald columns were at first produced using #2 Southern Yellow Pine, but the larger knot size, increased allowable wane, and the steeper grain angle produced a column that looked rough and had potential weak points near the larger and more numerous knots. Only #1 Southern Yellow Pine had the proper grain slope and limited knot size to meet the Gruen-Wald Classic specifications for the column base. The
.60 CCA treat also satisfies all model Building Code requirements for foundations.
Finding a treating plant that could deliver dimensional lumber treated and kiln dried to the correct moisture content for gluing proved to be exhaustive. The moisture content is extremely crucial to the glu-laminating process because the interstitial pores, if too full of water, cannot absorb the glue. If too empty, they absorb all the glue, potentially leaving a “dry joint”. To date only two treating plants in the Nation have been able to reliably provide this product to us and they supply 100% of our treated lumber for both Gruen-Wald plants.
The upper columns are typically made of machine stress rated 1650Fb Spruce Pine Fir because of its strength, stability and the small tight knots. Some builders prefer Southern Yellow Pine on the upper column and this is done on a special order basis.
Various ideas were explored for joining the several pieces of each ply together. Staggered butt joints have no strength at all for the spliced ply so that was rejected. Experimentation was done using metal (truss) connector plates, thin metal plates sandwiched between plies and splice blocks over the butt joints, but none developed the full section capacity of the several plies. The best solution was the structural finger joint. Although the most expensive to do, it was by far the best. Structural finger joints provide full continuity through the entire length of the columns, eliminating weak points where joints occur.
Because the Gruen-Wald Classic Column had never been made before, special equipment was designed by Duane and his trusty welder/machinist side kicks. When a manufacturing machine was not available to do the required job, one was invented. When a process needed enhancement or refining, the machines were modified or the process altered to produce the best product possible.
Now the question was, “How should we distribute Gruen-Wald columns?” Gruen-Wald chose the distribution system familiar to all in the lumber industry; Wholesale Distributors to Lumber Yards to Contractors. To this day, this is our primary distribution method and we are committed to it. This means that Gruen-Wald is fiercely loyal to our wholesale distributors and their customers and consider them partners, sending them leads from their area and working together for mutual success. Upon request, we hold “sales schools” where we teach the sales departments how to sell Gruen-Walds. We will also travel with their sales people to build confidence in the product. Gruen-Walds have proven to be a very profitable item to all in our distribution system.
Duane still likes to arrive at his office before 5:00 am to design new products and components on the “drawing board”, but he really loves it when the glu-laminating crew arrives at 6:00 am and he can interact with them to constantly improve the glu-lam process and work with the control quality people. Carefully designed revisions are being made that increase quality and reliability with constant attention to efficiency so that these columns make sense cost-wise as well as quality wise. Duane holds both a Bachelor of Science and Master of Science degree in Structural Engineering and holds Engineering registrations and certification in over 40 states. “Gruen-Walds” are accepted as The Standard of Excellence throughout the United States, Canada and Mexico.
Both the structural engineering company, Engineering & Technical Services, Inc., and Gruen-Wald Engineering Laminates, Inc., have adopted a “can-do” attitude. Engineering & Technical Services, Inc., has three Structural Engineers who think, breath, eat and sleep Post Frame Design and they know Post Frame Design as well as or better than any other firm in the Nation! The computer programs used to analyze each building were written by Engineering & Technical Services, Inc., Engineers and the results were verified with exhaustive hand calculations. The new International Building Code has also been integrated into the allowable stress tables used in the designs. You can be certain that the systems they develop for you will work safely and efficiently and the columns we manufacture will be of the highest quality. We guarantee it!
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