Whether you’re looking to create a unique space for your family or are in the market to renovate your current home, a mass timber house may be exactly what you need. Designed to combine hybrid construction methods and laminated dowel timber, this house provides the ultimate energy efficiency and sustainability.
Dowel laminated timber
Architects increasingly realize the benefits of 100% wood dowel laminated timber (DLT) as an energy-efficient building material. This technology is used for floors, ceilings, walls, and roof structures. It has superior strength and stability and is also highly versatile, which makes it ideal for composite systems. In addition, it is faster to assemble and install, and its use can be considered sustainable and environmentally friendly. The advantages of laminated dowel timber include its durability and ability to house pre-integrated acoustic materials and electrical conduits.
The mechanical properties of dowel laminated timber members vary depending on the lamella and dowel species used, the arrangement of the dowels, and the loading orientation of the structure. However, studies of the properties of DLT have been limited. Therefore, in 2004, BS EN 1995-1-1 (2004) was produced to guide the structural design of dowel laminated timber members using steel dowel fasteners. This guide provides information on the selection of dowels, the positioning of the dowels, and the use of adhesives.
While DLT has been manufactured in Europe for many years, the US has yet to adopt this mass timber product. Currently, glulam is more commonly used for beams and floor decks. Glulam is a composite of parallel layers of lumber glued together with structural adhesives. In addition, glulam can be used to form arches and columns. There are also a variety of other applications for glulam.
While dowel-laminated timber is relatively new to the United States, the development of this technology is gaining momentum in Europe. As a result, the United States is starting to take notice and will likely use it more in the future. Making dowel-laminated timber is more efficient than nail-laminated timber, which involves using nails or screws to hold boards together. A significant advantage is using a computer numerical controlled (CNC) machine to produce dowel laminated timber panels. These panels can measure as large as 3.7 meters by 18.7 meters. They can be used in various applications and are readily available from suppliers.
In 2012, Belleville and colleagues conducted an experimental study on the performance of dowel-laminated timber beams. Two species of timber lamellas were inserted into a glued timber beam, a bonded dowel laminated beam, and a welded dowel laminated beam. The study showed that the glued and welded dowel laminated beams had significantly lower bending stiffness than the nailed laminated beam. However, the dowel insertion angle did not considerably influence the bending stiffness.
Another study investigated the fabrication of dowel-laminated timber beams without adhesives. First, the authors inserted 56 beech dowels into two lamellas at a 30 deg angle to the longitudinal face of the lamellas. Afterwards, the dowels were conditioned by adding a layer of water-repellent coating. The conditioned dowels were then inserted into pre-drilled holes perpendicular to the posts. This compression of the dowels created a tight fit and increased the dimensional stability of the dowel laminated timber beam.
Hybrid construction
Using hybrid construction for mass timber house buildings has several advantages. It can be aesthetically pleasing, economical, and structurally sound. It can also help reduce the carbon footprint of a building. It can be combined with concrete or steel to provide a robust and sturdy structure. Finally, it can be constructed offsite, which means less mess and faster build times.
During the past few years, builders and architects have discovered that various building materials can combine to create an aesthetically pleasing, strong, and affordable building system. While wood has been used extensively in the construction industry for years, new technologies are making it easier to combine different materials into a symbiotic relationship that provides benefits for the homeowner and the environment.
Mass timber in a hybrid structure allows for a higher strength-to-weight ratio than traditional methods. It is also very energy efficient. For example, a building with a mass timber floor can achieve a rating of Passive House, which is the most efficient energy-efficient building design.
Combining wood and steel also offers extra support, which is essential in many applications. For example, wood gives off fewer greenhouse gas emissions than concrete, and it has a biophilic effect on the people living there. Adding spray foam insulation to stud walls and structural insulated panels can also enhance the thermal performance of a building.
With today’s codes, building a hybrid timber structure that can be as tall as 18 stories is possible. The new International Building Code (IBC) for 2021 will allow this construction. The IBC will also allow for low- and mid-rise office buildings and residential buildings under eighteen floors.
The new IBC will also include height expansions for mass timber, which will suit building designers and builders. In addition, the IBC will require that a concrete topping slab be installed over a mass timber floor, allowing for better fire resistance and thermal performance.
In addition to the increased height, the building will also have more wind hazards. However, the resulting structure will be more energy-efficient, with less embodied carbon during construction.
Hybrid construction for mass timber house buildings can be a cost-effective solution to complex designs. A sound-quality framing system is essential, as a home needs to be plumb, level, and square. Using prefabricated panels will reduce the time required to construct a home by 25%. It will also save money on foundation costs.
Depending on the architectural vision and local regulations, hybrid structural solutions may be more suitable than conventional construction. A knowledgeable builder, a well-thought-out project, and innovative wood-based hybrid solutions could make for a more sustainable and efficient building.
In the future, we may see more building structures that combine wood with other systems, such as steel, concrete, and podiums. Therefore, it is a good idea to consider all of these options before beginning a hybrid project, as it can help to ensure a successful project.
New York City’s Brock Commons Tallwood House
Designed to be the tallest contemporary wood tower in the world, Brock Commons Tallwood House, located on the University of British Columbia’s Point Grey campus in Vancouver, is now a reality. This 18-story student residence comprises glue-laminated timber (TLT) panels and a prefabricated facade. It will provide student accommodations and study spaces for up to 400 students. It is also designed to be LEED Gold certified. The building’s fabric is constructed from sustainably harvested Canadian wood.
When completed, the Brock Commons building will be a model for mass wood construction and the first application of mass-timber products in a residential high-rise. The TWBDA, or the Tall Wood Building Demonstration Initiative, was launched by Natural Resources Canada in 2013 to showcase wood-based solutions for high-rise buildings. This research has contributed to a body of knowledge that will address many challenges associated with using wood in construction.
The Brock Commons building was a collaborative effort of several organizations, including Acton Ostry Architects, Structurlam, Fast + Epp and Urban One Builders. It also involved other industry partners and organizations. For instance, CadMakers provided construction management and design services for the project. They worked closely with all stakeholders to ensure the building was built on time and within budget. Using the Dassault Systemes 3DEXPERIENCE(r) platform on the cloud, they optimized processes throughout the value chain of the project. This enabled the project team to identify issues in a 3D environment and resolve them before they reached the site.
The Brock Commons project also participated in the International Wood Construction Press Awards. In addition, it was selected for the Juror’s Choice Award for Technical Innovation. This was because the project resulted from a highly collaborative integrated design process that leveraged the strengths of both wood and steel.
This unique building combines the strength of cross-laminated timber panels with the beauty of wood columns. The building fabric is delivered in prefabricated shapes that meet fire codes. These panels can be manufactured in up to 40-foot lengths. They are stronger and more fire-resistant than natural wood. This technology has been around for a couple of decades.
The construction process for the Brock Commons building was significantly shorter than that for a traditional concrete building of the same size. As a result, it was completed four months faster than a concrete building of this size. As a result, the building also saved 679 tons of carbon dioxide emissions. This is equivalent to taking 511 cars off the road for a year.
The project’s design was developed to meet UBC’s Tall Wood Building Regulation, which was designed to protect the health and safety of the building’s occupants. The building’s structure had to be tested and verified to comply with the regulations by independent peer review. A team of experts from Canada and around the world reviewed the building.