May 6, 2019
Freres Lumber’s Mass Plywood Panels (MPP) have been put through rigorous testing, gaining several engineered wood certifications and proving to be a high preforming material for multi-story construction. So, what’s next for MPP?
Beams and Columns
We are currently certified for laminated veneer lumber (LVL) and MPP. These two certifications are the foundation for many products to come.
The next round of testing will be for deep beams on edge, with proposed testing for beams up to 6-feet deep by 12-inches wide, with possible spans of over 100 feet! With MPP’s minimal shrinkage and swelling, we should be able to splice these beams together with a steel knife plate and screws without concern of cracking (as shown below).
Screw technology has boomed alongside mass timber making these knife plates easier to install and stronger. These screws, as opposed to bolts, are smaller in diameter and a tighter fit and, thus, can disperse the load better to create a stronger connection while minimizing cracking.
Soon after deep beams on edge, we will be working on a certification that will give us the ability to produce beams (in plank orientation) and columns up to 24-inches thick, which will be processed in a highly automated way that is not common within the industry. The processing line will be able to cut diagonals for structural and architectural reasons. With steel knife plates and the processing line we could potentially replace structures as shown below with wood.
Different Grades of LVL and MPP to Support a Variety of Applications
As of today, we have three different grades of LVL (1.0E, 1.55E, 1.6E) and one MPP (1.6E). LVL is the building block of MPP. We can take these different grades to build up the MPP. This method is common with glulam beams. The higher quality, more expensive wood to be utilized on the outside of the product, and places the lower quality, less expensive wood at the center of the product, resulting in a product with similar structural properties, but at a much lower production cost.
Currently, Freres Lumber’s MPP is all 1.6E grade, which uses G1, the highest grade of veneer. This means we can do the same thing as glulam by putting the highest grade on the outside of the beam and the lower grade can be used in the middle (see image below). This increases the affordability of our mass timber product without sacrificing its performance.
Raising the Potential of MPP
Our plan is to maximize MPP’s structural concept to its full potential. We will soon be testing a more traditional LVL product that will be a 2.0E (all the veneers running lengthwise, i.e. no cross plies). This can be used as the outside layers of MPP, resulting in a stiffer, stronger panel. To build up the strength across the width of the panel we can place the LVL crosswise in the layup (currently lamellas are laid longwise over the length of the panel). This will provide a better two-way span that is able to eliminate the beams and create a panel that spans four columns.
New Applications to Explore
There are many more MPP design possibilities to discover. We see efficiency and versatility in the different layup options and the beam and column processing lines. While there’s a lot to look forward to with MPP, the current LVL and MPP product capabilities already offer a viable economic, and environmental solution to many building projects.