* Glu-Laminated wood is multiple plies of dimensional lumber that are face glued with a structural adhesive that holds them in permanent intimate contact. These plies may be extended by using structural finger joints that allow continuous lengths to 70’ and more. These structural finger joints must be manufactured to ANSI/AITC specifications.
To meet AITC/ANSI A190.1 standards, the manufacturing must be done under third party certification by a recognized organization such as APA EWS or AITC.
This is critical because building codes require it and it provides quality control of this highly technical manufacturing process. Always demand this quality control or you are gambling with people’s lives, property values and your own viability as a purchasing company.
* What types of wood can be structurally glued?
There are many variations of wood used for glu-lam products. Typically, SYP and Doug Fir are used for their strength and beauty. These may be treated or untreated. Doug Fir must be incined to treat which leaves marks on the surface.
Cedar is often used in lieu of a treated product for exterior use and also for its beauty and aroma. Red Cedar, Alaskan Cedar, etc. are common types used.
Hardwoods such as oak are often used because of beauty and durability. Hardwood products require special attention such as pre-drilling for even nails, screws and small lag bolts. They also are not treatable so must be sealed and protected from excess moisture.
Spruce Pine Fir (SPF) is often used for lower stressed beams and columns and is often used for the middle section of beams with high strength plies on the top and bottom. SPF does not treat well.
* Why use Glu-Lam instead of Solid Sawn timber?
First off, glu-lam members are substantially stronger than sold sawn members.
Secondly, large solid lumber beams must be cut from large trees. This limits the supply to older trees of which there are fewer and fewer around.
Third, in a solid beam or column, any knot or other anomaly usually runs through the entire member. When this is near the edge, the member is substantially weakened. Since glu-lam member plies are randomly assembled, these anomalies never continue through the entire cross section.
Fourth, solid sawn members are prone to twisting, splitting and warping when drying out. Glu-Lam plies are all kiln dried prior to gluing to within a few points of equilibrium moisture content of the structure they will be placed in. Also, the grain patterns oppose each other and therefore hold each other straight.
Face checking may occur in glu-lam products but it is never a structural problem.
* Will my local code official allow these products in buildings in their jurisdiction?
If the product is manufactured under the supervision of a third party group such as APA EWS or AITC, they meet ANSI A190.1 standards and thus meet IBC & IRC and most state specifications. Therefore they should be accepted by all building officials.
On a rare occasion, an inspector, who is not familiar with glu-lam products wants to communicate with a structural engineer registered in the state the project is in. Gruen-Wald provides this service for you. On rare occasions, elaborate calculations may require added fees, but very seldom does it become this extreme.
* Where can we find Engineers who understand engineered wood products who can produce an economical but structurally safe design?
Gruen-Wald Engineered Laminates has you covered in this. Our Engineers are registered in 42 states and are covered in the remainder by reviewing Engineers. Call for a quote or e-mail your request/inquiry.
* Where can I find designs and product for Heavy Timber Frame Structures?
Once again, Gruen-Wald has you covered. Our design department will work with you to obtain the desired look. Our estimators will give you a quote and upon acceptance, our skilled Hundegger operators will build the individual elements and pre-fit to insure trouble free field assembly. (See photo gallery)
* How long will timber products last?
There are wood frame structures in existence that are over 1500 years old. Many European cities have 1000+ year old structures.
If properly maintained, a wood structure will typically outlast steel and concrete structures.
* Is it environmentally friendly to use wood instead of steel, concrete, recycled plastics or other such products?
Wood is the only truly renewable resource to use in buildings. More trees are being planted each day than are being harvested (about 6 to 1).
These beautiful living organisms remove carbon from the atmosphere, store it in their fibers and breathe out pure oxygen. Then, when harvested they store tons of carbon for the life of the structure.
If the structure is to be demolished, these wood members may be recycled and used to build another structure.
* What is the carbon footprint of a wood structure compared to other materials?
Wood is the most efficient product of all other typical products.
Wood compared to steel, concrete, aluminum and recycled plastics has the smallest carbon footprint!
Wood structures are also superior for insulative properties.
* Do we need to see steel connector plates on the face of our timber structure joints?
Gruen-Wald Engineered Laminates has developed a system of “stealth” connector plates that are hidden within the members. Our K-2 Hundegger also does mortise and tennon (pegged) connections as well as dove tailed connections so in you beautiful wood structure you only see wood!
* Is the Gruen-Wald Heavy Timber very expensive?
We have competed with and beat conventional framing prices on such diverse structures as homes, schools, churches, dairy barns, cattle barns and retail spaces. Heavy timber structures typically save 50% on labor (and time).
* How long a span can you build?
We have done up to 120’ spans for trusses but typically they are practical to 100’.
* How long does it take to manufacture and erect a Heavy Timber Structure?
Manufacturing usually takes four to eight weeks depending on the size, complexity and erection is generally 1/3 to ½ the time for other construction.
For example, a 4 story, 12,500 square foot heavy timber frame house was erected in two weeks of working time with 3 laborers and a crane operator using SIP panels for walls and roof.
A 70,000 square foot dairy free stall building super structure was put up in 3 weeks time.
* Can Heavy Timber structures be fire rated?
Yes, by proper design, the Heavy Timber structure can be rated 1 hour. It should be noted that steel supports will twist and fall suddenly in a fire while Heavy Timber will char and burn very slowly, giving time to evacuate and allow fire fighters access to fight the fire.
The wood members are often re-usable after the fire while the steel members are generally rated un-usable and must be replaced.
* Can the Heavy Timber members be pre-finished?
Yes. We recommend pre-staining and sealing/varnishing prior to shipping. From our experience unfinished members almost always require field sanding to remove water marks, no matter how carefully they are wrapped. With a finish, even mud is easily wiped off and the finished product is ready for final inspection. This usually costs an additional $0.35 to $0.50 per board foot.
* Can Heavy Timber framing be used with Structural Insulated Panels (SIP) walls, roof and floors?
Yes. Ideal spans for SIP panels are from 4’ on center to 16’ on center. For large structures we recommend 12’ to 16’ on center for economy. This combination gives you ideal insulative characteristics, beauty and substantial time and labor savings.
* Can we use conventional framing between the glu-lam beams and columns?
Yes. Our structures are often coupled with paneled inserts, I-Joist, etc.