Mar 7, 2024 - 3-5 minutes
Improve Mass Timber and Engineered Wood Performance and Processability
Find out how structural adhesives for mass timber and engineered wood meet performance and processing needs, enabling you to utilize renewable resources instead of traditional building materials such as steel, wood, and concrete.
In an effort to reduce environmental impact, you, like other building material manufacturers, may want to use alternative building materials to traditionally used steel, wood or concrete. This is because they have environmental drawbacks, such as:
- Steel: Manufacturing steel requires high levels of energy, which results in high carbon emissions. It is also a heavy-weight material that increases emissions during transport.
- Wood: While wood is a renewable resource, which aids the environment, it is not possible to keep up with demands solely by growing trees for large timber products.
- Concrete: Manufacturing concrete requires breaking down rocks and mixing with other materials, which utilizes high levels of energy to complete. It is also a heavy material to transport, which may result in additional carbon emissions compared to transporting lighter materials.
Mass timber and engineered wood, however, are a popular alternative option to consider. They provide an opportunity to use smaller pieces of wood of various quality levels, which are renewable resources, including pieces that would otherwise be scrapped. In this way, you can make the most of the current timber.
However, while mass timber and engineered wood are more sustainable options than steel, solid sawn wood and concrete, it can be difficult to achieve the needed end-product performance with cost-effective manufacturing processes.
That doesn’t have to be the case.
Learn how structural adhesives for mass timber and engineered wood help you meet performance and processing requirements.
How Structural Adhesives Meet Mass Timber and Engineered Wood Performance Needs
Mass timber and engineered wood include:
- Cross-laminated timber (CLT) and Glulam
- Wooden I-Joists and Structural Finger Joints
While the level of performance needed may vary based on application, it's important that structural adhesives help mass timber and engineered wood meet the following criteria:
Durability
Durability is a key performance need for mass timber and engineered wood applications. Structural adhesives’ high strength properties can allow you to use smaller wood pieces to form large timber products that may otherwise never get used and lead to material waste. Additionally, their strength helps mass timber and engineered wood applications remain firmly intact during production steps, transport and installation.
Further, this strength helps increase overall product longevity. This results in fewer repairs or replacement materials needed over time, which further allows mass timber and engineered wood to reduce environmental impact.
Heat and Fire Resistance
Structural adhesives should be capable of passing PRG-320 standards for sheer, fire and creep testing, to prove they can address these necessary performance needs for enhanced safety:
-
Thermal stability: Structural adhesives undergo testing to prove they can withstand high temperatures. This helps ensure they’ll maintain bond strength and structural integrity.
- Fire resistance: In addition to overall thermal stability, some mass timber and engineered wood applications may specifically require fire resistance; certain structural adhesive formulations are capable of withstanding flames and extreme temperatures in fire-prone environments to further enhance durability.
Environmental Resistance
Structural adhesives address a variety of environmental resistance requirements including:
- Moisture: It’s common for mass timber and engineered wood to be exposed to moisture throughout the products’ overall lifespan, which can compromise structural integrity. Designed to resist moisture penetration, structural adhesives help prevent swelling, warping and delamination to maintain high quality.
- Temperatures: Structural adhesives are formulated to maintain properties when mass timber and engineered wood are subjected to temperature changes, helping prevent adhesive degradation or reduced bond strength.
- Chemicals: It’s possible that some mass timber and engineered wood applications may come into contact with solvents, cleaners or industrial fluids. Structural adhesives are designed to resist degradation from aggressive chemicals.
How Structural Adhesives Meet Mass Timber and Engineered Wood Processing Needs
Your mass timber and engineered wood application needs will require your chosen structural adhesives to include:
Reduced Press Times
In order to keep a seamless production line running that involves large-scale products like end-use mass timber and engineered wood products, structural adhesives can be formulated to have a customized open assembly time, allowing reduced press times. This includes providing:
- Equipment compatibility: Structural adhesives offer workability with various equipment processes including bead, roll coat and swirl application systems. This allows you to use equipment you already own to reduce production costs.
- Room temperature application: Many structural adhesives can be applied and cured at room temperature, helping reduce production complexities, energy consumption and overall costs for specialized heating equipment.
Fast Curing
Structural adhesives are formulated to cure quickly to increase assembly speeds, allowing high-volume productions.
Versatility
Structural adhesives are compatible with different wood substrates that may be combined into one mass timber or engineered wood product, such as wood veneers, particle board or plywood. This allows you to use various types of wood substrates in one production line, which streamlines operations. It also helps you know that you’ll still have a strong bond if they all end up in the same product.
Choosing the Right Structural Adhesive Formulation Based on Application
Cross Laminated Timber (CLT) and Glulam
Moisture-cure polyurethane structural adhesives address key criteria for CLT and Glulam including:
Performance:
- High durability: This adhesive technology provides excellent strength to extend the lifespan.
- Heat and fire resistance: Moisture-cure polyurethane structural adhesives coupled with a primer can meet the most stringent fire testing, which is particularly important for CLT and Glulam face laminating. This testing includes passing self-insulating tests to prove the structural adhesives can survive extensive burn events under practical loaded conditions.
- Environmental resistance: Moisture-cure polyurethane structural adhesives contain moisture-reactive components that help seal the joint to protect against moisture and prevent swelling, warping or decay over time. This technology can also withstand a range of temperatures, helping maintain structural integrity when CLT or Glulam is exposed to temperature changes.
Processing:
- Reduced press times: Moisture-cure polyurethane structural adhesives can be formulated to provide specific open times that allow you to minimize ambient press times, maximizing productivity.
- Fast curing: Single-component urethane adhesives utilize moisture from the wood and the environment to accelerate adhesive cure. This provides cost efficiencies because it eliminates the need to use heated equipment for the curing process.
- Versatility: Moisture-cure polyurethane structural adhesives are compatible with SPF, Douglas fir and southern yellow pine to enable expanded wood substrate options.
Additionally, this solution is solvent-free and formaldehyde-free, further reducing the overall carbon emissions released during manufacturing.
Wooden I-Joists and Structural Finger Joints
Structural polyurethane and water-based adhesive technologies meet key demands for wooden I-joists and structural finger joints such as:
Performance:
- High durability: These solutions can achieve high bond strength for proof loading with room temperature cure, helping to create long-term durability while reducing overall energy usage.
- Heat and fire resistance: Similar to CLT and Glulam applications, I-joists and finger joints are tested for the most stringent fire testing including self-insulating tests to proving adhesives can survive extensive burn events under practical loaded conditions.
- Environmental resistance: Structural polyurethane and water-based adhesive technologies offer outstanding resistance to moisture and humidity, helping prevent damage for long-term stability.
Processing:
- Reduced press times: These technologies offer fast green strength that helps reduce press times for a complete cure.
- Fast curing: Based on the adhesive technology used, a full cure is achievable in 8 to 24 hours at room temperature. Unlike other competitive options that cannot cure at ambient conditions or require post-cure heating, structural polyurethane and water-based adhesive technologies allow you to reduce overall energy usage.
- Versatility: Structural polyurethane and water-based adhesive technologies are compatible with OSB, laminated veneer lumber (LVL), SPF and additional wood substrate options.
Additional Benefits:
- Color Neutrality: Structural polyurethane and water-based adhesive technologies all offer color neutrality. By providing a wood-colored bond line, these adhesive technologies appear transparent in between wood pieces. While the wood itself can vary in color, a neutrally colored adhesive is helpful in maintaining overall aesthetics, especially if the mass timber or engineered wood is eventually stained or painted during installation.
- Improved Accessibility: These adhesive technologies are all produced in North America, providing ease of supply for fast local delivery times. This can reduce logistical complexities to receive the necessary materials to manufacture mass timber or engineered wood products.
How Bostik Helps:
As the adhesive solutions segment of Arkema, Bostik offers decades of product performance and processing expertise with its portfolio of mass timber and engineered wood bonding solutions, helping address demands for CLT, glulam, wooden I-joists and finger joints. In turn, this will help improve overall sustainability in building construction projects.
- ISOSET™ HX adhesives are single-component, moisture-cure polyurethane adhesives designed for CLT and glulam face laminating applications. This solvent and formaldehyde-free solution provides excellent durability, utilizing a primer to meet the most stringent fire testing standards.
- ISOSET™ PEP adhesive technology is based on polyurethane chemistry as a two-component system for wooden I-joists and finger joints. Offering a full cure in 8 hours at room temperature, this solution offers fast green strength with excellent bonding properties.
- ISOSET™ EPI adhesive technology is based on water-based latex resin that bonds with excellent creep, shear and tensile properties for wooden I-joists and finger joints. Offering durability with moisture and humidity resistance, this technology provides a full cure in 24 hours at room temperature to help reduce energy usage.
Along with our solutions, our technical support team is here to provide trial testing and troubleshooting to ensure our technologies offer optimal performance and processing efficiencies. We can customize formulations to help ensure specific application needs are met.
Interested in learning more about how structural adhesives can address demands in mass timber and engineered wood applications? Contact a Bostik expert to learn how our solutions can directly achieve sustainability, high performance and easy processing.
Other relevant content:
©2024 Bostik, Inc. All Rights Reserved
All information contained herein is believed to be accurate as of the date of publication, is provided “as-is” and is subject to change without notice. To review our full U.S. Legal Disclaimer, visit: https://bostik.com/us/en_US/privacy-policy/legal-disclaimer