Mass Ply


Mass Ply is a patented, veneer-based engineered wood product developed by Freres. Mass Ply is a mass timber panel assembled by combining thin layers of stress-rated Douglas Fir veneer, in the long and cross direction, creating a large-format wood platform that is then prefabricated to exact dimension with a CNC machine. Mass Ply is strong, fire-resistant, and lighter per volume than traditional building materials such as concrete or steel.

Mass Ply is a sustainable building product that gives superior strength and stiffness relative to other products on the market. Mass Ply allows for small increments of thickness thus saving overall cost of material while maintaining competitive price per volume. The panel is a prefabricated in the factory for fast install on the jobsite. It can also be left exposed, giving the building the biophilia benefits to the tenants. Also, because it is a veneer-based product, it utilizes the raw material more efficiently and lends itself to harvesting practices that are considered to be more environmentally friendly.

Although its name may suggest otherwise, the Mass Ply Panel is composed of 1″ x 4′ x 8′ layers of Laminated Veneer Lumber (LVL), a veneer-based engineered wood product certified under ASTM D5456. The LVL layups have cross plies, which allow the mass timber panel to have strength and stability across both axes of the panel. Our higher performance layups have more long plies than cross plies to achieve greater divs. The 4′ x 8′ sheets are scarf jointed together to achieve a length up to 48 ft. A width up to 11’10” is achieved by using 4′ and 2′ wide panels and staggering the joints as each course gets laid up to the desired thickness.

Mass Ply is extremely versatile. Mass Ply is used for roof, floors, walls, beams, columns and even furniture. While it can be cut to almost any shape and size, the panel size after trim is limited to 11’10” wide by 48′ long, up to 24.48″ (24-ply) thick or as little as 2.04″ (2-ply). Mass Ply products can be used for almost any structural wood element in a mass timber building. The CNC machine, which is typically utilized for floor and roof panels, is limited to a 12″ panel thickness. Anything above 12″ goes to the beam and column line where it is cut to length and width.

There are 108 veneer layers within a 12″ deep Mass Ply. Each layer of veneer starts out at .125″. There is some compression from the layup process of the 4′ x 8′ LVL sheets. In addition, some of the outer veneers are sanded down to ensure a good bond during the Mass Ply layup. Each one of these veneers are stress rated and can be orientated in the long and cross direction. We are continually expanding our product with different grades to optimize the panel for the application at hand.

Freres Mass Ply can be used as pre-fabricated mass timber floor, roof or wall panels, and for beams and columns to allow rapid construction on multi-story structures. Mass Ply has been used in single family homes, industrial buildings and bridges. Mass Ply is available in thicknesses ranging from 2″ to 12″ in 1″ increments. Mass Ply Lam (MPL) products are available in thicknesses up to 24 inches.

The APA Product Report, a PR-L325, has our structural values for our panels, beams and columns. Table 1 is used for panel design, Table 2 is used for beam and columns design, where Table 3 is used for fastener design for panels, beams and columns. Visit to view the product report and design values. Please note that we are continually adding new products, so always check for updated reports.

Freres has conducted extensive product testing on Mass Ply for structural, fire, acoustics and moisture stability. The APA has performed extensive testing to certify our products under ASTM D5456 and PRG 320. This combination of certifications is unique to Mass Ply compared to CLT as we have to comply with the rigorous testing of both the CLT and LVL standard. We are also working to establish design values outside those required by those standards with partners at Oregon State University, The Tallwood Design Institute and other labs across the country. These tests include seismic loading, fastener performance, impact loading, blast resistance, ballistics, acoustics and additional fire testing.

CLT is a type of mass timber panel constructed of either machine-graded or visually graded dimensional lumber, typically consisting of odd layers of dimension lumber oriented perpendicular to one another and then glued to form structural panels.

Mass Ply uses veneer as the primary raw material to create an LVL panel, which is then used to create a mass timber panel; whereas CLT uses dimensional lumber as the primary raw material.

Mass Ply tends to be stronger and stiffer than most grades of equivalent thickness CLT. Each veneer is electronically graded. Numerous layers of veneer effectively distribute and reduce the effect of defects such as knots. Greater flexibility in lay ups means that applications can be optimized both structurally and economically. As a result, the panels have a more predictable performance than lumber-based products.

The minimum design values for Mass Ply exceeds the minimum design values of E2 CLT defined by PRG-320 in each comparable thickness in major force direction. E2 CLT is the most comparable grade of CLT in terms of engineering and species that we have to compare to Mass Ply.

Mass Ply uses about 20% less wood than CLT and is as strong as or stronger than other SCL products. In addition, the dense layering of wood veneers in Mass Ply can result in high levels of thermal insulation. Mass Plys can be produced in varying lengths and thicknesses from small-diameter, fast-growing trees, negating the need for using larger trees to produce larger formatted pieces of lumber.

Finally, wood framed buildings have been typically limited to four stories due to fire concerns. The predictable char rate of Mass Timber Panels allows buildings to be built taller with wood, allowing code approved multi-story structures out of wood up to 18 stories anticipated in the next iteration of the International Building Code (IBC).

Mass timber panels, like CLT, are an extraordinary development that will allow the manufacture of pre-fabricated structural wood panels to construct multi-story structures rapidly. With years of experience in the veneer business, we realized we could produce a better product in this category that would open doors from a building and construction standpoint, would be better for the environment and be more cost effective than current market offerings.

Mass Ply uses 20-30% less wood than CLT and is as strong as or stronger than other LVL products. In addition, the dense layering of wood veneers in Mass Ply can result in high levels of thermal insulation. Mass Plys can be produced in varying lengths and thicknesses from small-diameter trees, negating the need for using larger trees to produce larger formatted pieces of lumber.

Finally, wood framed buildings typically have been limited to five to six stories due to fire concerns. The predictable char rate of mass timber panels allows buildings to be built taller with wood, allowing code approved multi-story structures out of wood up to 18 stories and even taller with special approval.

The primary bond for each LVL lamella created uses phenol-formaldehyde resin in a hot press. The secondary bond is created using a melamine formaldehyde cold-press resin.

All resins used within Mass Ply are CARB-compliant. There is no additional formaldehyde off-gassing beyond what is normally observed in wood. For more information, please visit, APA Technical Note: Formaldehyde and Engineered Wood Products.

Our standard grade is visually appealing since we visually grade the veneer. It has a sanded finish and has closed knots less than 1″ in diameter.
Our upgraded appearance is our HD Face, which limits the knot counts to eight or fewer per 4′ x 8′ sheet and the size of the knots to ½” in diameter. Freres has designed the Mass Ply production process to allow “skinning” the Mass Ply panel with any finished architectural panel for appearance characteristics. There are limitations with this option. For more information, reach out to the sales team.

Mass Ply is made to handle exterior exposure criteria much like plywood and other engineered wood products. It can be exposed during construction periods, but precautions must be taken to minimize exposure, and Mass Ply must be dried out before putting protective covering over it. Expansion and contraction from moisture need to be considered as well.

Please refer to this blog that provides expansion and contraction data and discusses the benefits of Mass Ply in relation to moisture. Mass Ply is not meant to be permanently exposed to the elements. Appropriate siding products should be used in conjunction with the structural panels.

The standard Mass Ply format is flat. We can route out a curve on the face of the panel. However, the panel thickness is limited to 7″. We do not have direct test data for this type of application.

Increasingly, mass timber is being used as an alternative to concrete and steel construction for mid-rise building construction. Mass timber products have a number of advantages over steel and concrete. Mass Plys are renewable, have a significantly smaller carbon footprint, have more aesthetic value and are often cost-effective because they are much faster to install.

Many of the traditional timber joints may be used when constructing with Mass Ply. Spline joints, ship lap (half-lap) joints, and the like are very common when connecting one Mass Ply panel to another. The particular joint used will depend on the specific application.

Mass Ply is transported by either rail or by truck. Rail loading facilities have been constructed at our manufacturing facility so that we may load a variety of rail cars for shipping long distances. Due to limitations with rail transportation, please contact our sales team.

Mass Ply, as well as other mass timber products, are not designed to be used as exterior construction elements. Weatherproof materials should be used to protect structural products from the weather.

The idea for Mass Ply began in the summer or 2015. By 2017, the first Mass Ply facility was online.

Freres patented our Mass Ply Panel engineered process. Freres’ Mass Ply has earned patents in the United States, Canada, Australia and New Zealand. Additional patents are pending worldwide.

No. This is a new product designed from the ground up by the Freres family. We have a variety of engineered wood products including the Mass Ply Panel, Mass Ply Lam (beams and columns) and Mass Ply Industrial (mats).

Freres is only the third company in the United States to be certified in accordance with PRG 320. Mass Ply is the only patented product in this category on the market.

The biggest obstacle we have faced is that Freres is blazing a new trail with Mass Ply. We owe thanks to the many partners that have helped make Mass Ply a reality and success.

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