Materials Chat #1 – Engineered Timber Products

In this blog post, we will explore a few types of engineered timber, their strengths, and delve into some of the reasons why engineered wood can be better than steel or regular wood for certain applications.

Engineered timber is a term that refers to a range of wood products that are made by bonding together wood strands, veneers, fibers or particles with adhesives under high pressure and temperature. Some examples of engineered timber products are laminated veneer lumber (LVL), laminated strand lumber (LSL), oriented strand board (OSB), plywood, particleboard and medium-density fiberboard (MDF).

Engineered timber has many advantages over traditional solid wood, including some advantages over steel.  Here are some of the main benefits of engineered timber:

  • Strength and stability: Engineered timber products have consistent dimensions and properties, unlike solid wood which can vary in quality, shape and size due to natural defects, moisture content and grain orientation. Engineered timber products can also be designed to have specific strength and stiffness characteristics by adjusting the orientation, thickness and arrangement of the wood layers or strands. For example, LVL and LSL are engineered to have high strength along their length, making them ideal for beams, columns and headers. OSB and plywood have high strength in both directions, making them suitable for sheathing, flooring and roofing.
  • Sustainability: Engineered timber products are more environmentally friendly than solid wood because they use less raw material and produce less waste. Engineered timber products can be made from fast-growing plantation trees or from wood residues that would otherwise be discarded or burned. Engineered timber products also store carbon dioxide that was absorbed by the trees during their growth, reducing greenhouse gas emissions. Additionally, engineered timber products can be recycled or reused at the end of their service life.
  • Versatility: Engineered timber products can be used for a wide range of applications in residential, commercial and industrial buildings. They can also be easily cut, drilled, nailed, screwed or glued to fit different shapes and sizes. Engineered timber products can also be combined with other materials such as metal connectors, concrete or insulation to create composite structures that enhance performance and functionality.
  • Aesthetics: Engineered timber products can offer a variety of finishes and appearances that suit different tastes and styles. Some engineered timber products have natural wood grain patterns that add warmth and beauty to any space. Others have smooth surfaces that can be painted or laminated with decorative veneers or coatings. Engineered timber products can also create interesting architectural features such as exposed beams, vaulted ceilings or curved walls.
  • Moisture Resistance: One of the main benefits of engineered wood is its resistance to moisture. Unlike steel, which can rust and corrode when exposed to water, engineered wood does not absorb water and will not swell, decompose or develop mold over time. This makes it ideal for humid or rainy climates, as well as for areas that are prone to flooding or water damage.
  • Weight and Installation: Engineered wood is also lighter than steel, which can reduce the cost and complexity of transportation and installation. According to EDCO Products, engineered wood weighs about 150-200 lbs per 100 sq. feet, while steel weighs about 100 lbs per 100 sq. feet. This means that engineered wood requires less structural support and less labor to install than steel.

Engineered wood also has a more flexible installation process than steel. Steel requires precise measurements and alignments, as well as welding or bolting to join the pieces together. Engineered wood can be cut and nailed easily on site, with little to no caulking required . Engineered wood also allows for overlapping of siding panels, which can accommodate expansion and contraction due to temperature changes.

There are many types of engineering timber. Below is a quick summary of a few popular options. This list is not exhaustive, and does not include options such as Nail-Laminated Timber, Parallel Strand Lumber, or Mass Plywood Panels.

  • LVL stands for laminated veneer lumber. It is made by bonding thin layers of wood veneers together with adhesive under heat and pressure. The grain of each layer is parallel to the length of the product. LVL is strong, stiff and stable. It can be used for beams, headers, joists and columns.
  • LSL stands for laminated strand lumber. It is made by bonding strands of wood together with adhesive under heat and pressure. The strands are oriented randomly to create a homogeneous product. LSL is lighter than LVL but less stiff and strong. It can be used for studs, plates, rim boards and stair stringers.
  • Glulam stands for glued laminated timber. It is made by bonding individual pieces of lumber together with adhesive under heat and pressure. The grain of each piece can be parallel or perpendicular to the length of the product. Glulam can have various shapes and sizes depending on the design requirements. Glulam is flexible, durable and aesthetically pleasing. It can be used for arches, trusses, bridges and roofs.
  • Cross-laminated timber (CLT) is made by gluing together layers of kiln-dried lumber in alternating directions. CLT is a prefabricated solid wood panel that can be used for long spans in walls, floors and roofs. It has superior acoustic, fire and seismic performance compared to other materials. CLT panels can consist of three, five, seven or nine layers of dimension lumber , with thicknesses ranging from 100 to 300 mm (4 to 12 in) and widths ranging from 1.2 to 3 m (4 to 10 ft). CLT is also manufactured according to the ANSI/APA PRG 320 standard, which provides requirements for structural adhesives, appearance grades and stress grades.
  • Plywood is made by gluing several layers of wood veneers at 90-degree angles to each other. Plywood is very strong and versatile and can be used for indoor and outdoor projects. It has a cross-grain design that makes it resistant to cracking and shrinking.
  • Oriented strand board (OSB) is made by compressing layers of wood strands with adhesives in specific orientations. OSB is similar to particle board but has better structural properties and nail holding ability. It is typically used as roof, wall and floor sheathing, as well as for prefabricated wood I-joists and structural insulated panels. OSB panels can range from 100 to 500 mm (4 to 20 in) in thickness and from 1.2 to 3 m (4 to 10 ft) in width. OSB is manufactured according to the CSA O325 standard in Canada and the ANSI/APA PRG 320 standard in North America.
  • Particle board is made by compressing sawdust, wood chips and other wood waste products with synthetic binders. Particle board is one of the cheapest engineered woods, but it is not very durable or moisture resistant. It has a chipped appearance and a smooth surface that can be easily cut and painted.
  • High-density fiberboard (HDF) is made by pressing pulped wood waste, chips and other products with resins and adhesives at high temperatures. HDF is stronger than plywood and more resistant to moisture and temperature changes when treated properly. It has a smooth surface that makes it suitable for flooring applications.
  • Medium-density fiberboard (MDF) is similar to HDF but less dense and more flexible. MDF is easy to work with and can be shaped into various forms. It has a smooth surface that can be painted or laminated with different finishes. MDF is often used for furniture, cabinets, doors and panels.
  • Blockboard is made by gluing strips of solid wood between two layers of plywood or veneer. Blockboard has good dimensional stability and strength, but it can warp if exposed to moisture or heat. Blockboard is often used for making doors, shelves, tables and benches.

Conclusion

All of this does not mean that steel is inferior or obsolete as a building material. Steel still has its own strengths such as durability and strength-to-weight ratio. The choice between engineered wood vs steel vs regular wood depends on factors such as budget, functionality, aesthetics, and personal preference.

As you can see, engineered timber has many benefits that make it a smart choice for your next project. However, before you decide to use engineered timber products for your specific needs, you should consult an expert who can advise you on the best type, grade, quality and installation method for your situation. Sinitski Structural Engineering Ltd. can do just that!

If you are interested in learning more about engineered wood vs steel siding comparison, you can visit these websites:

Sources:

https://www.constructionspecifier.com/specifiers-guide-benefits-engineered-wood/

https://www.cdmg.com/building-faqs/wood-buildings-versus-steel-buildings

https://www.reminetwork.com/articles/benefits-of-engineered-wood/