Among the changes in material technology that are constantly altering the architectural landscape, one of the most popular - and most dramatic - is the idea of the timber skyscraper. And with vocal advocates like Benton Johnson of SOM and Michael Green leading the discussion with projects like the Timber Tower Research Project, the wooden highrise is on the verge of becoming a mainstream approach.
To further the conversation in the USA, the US Department of Agriculture, working in partnership with Softwood Lumber Board (SLB) and Binational Softwood Lumber Council (BSLC), has recently launched the Tall Wood Building Prize Competition, an ideas competition with a $2 million prize. To find out more about tall wood buildings, we caught up with Oscar Faoro, Project Manager of the competition. Read on after the Break for our interview and more details on how to enter.
ArchDaily: What are the advantages of mass timber buildings over conventional tall building construction?
Oscar Faoro: Besides the sustainability advantages that are well known, there are a number of significant cost savings that potentially can be realized by utilizing mass timber technologies.
We have yet to fully understand all of the advantages from a U.S. perspective, but from our research and understanding of the European and Australian experiences we can say there are two significant cost saving benefits. The first is a potential foundation cost savings which can be realized if soil conditions are poor. A mass timber wood structure is lighter than a conventional structural steel or reinforced concrete building, therefore requiring less effort and material to build the foundation with no compromise to the structural integrity of the overall project. The second is the potential savings from the speed of erection of the super structure and a quicker overall construction process. This is possible only if the buildings’ design, system integration and material selection lends itself to maximum offsite prefabrication.
AD: What are the advances that are making tall mass timber wood buildings a reality in recent years?
OF: The advances and improvements in design details and specifications that are making tall mass timber buildings a reality today are stemming from the results of scientific information and data generated from full scale fire, seismic, durability, acoustic and vibration tests being conducted internationally by researchers and engineers.
These experts are beginning to collaborate and share their results with interested U.S. parties, and in turn our engineers are now interpreting and applying the results into a North American context. Additionally, gaps in the existing research are being identified and filled with new scientific research and results.
Advances in wood connectors, hybrid materials and building systems, the commercialization of Cross Laminated Timber (CLT), and off-site prefabrication have all provided more options for the safe and effective design and construction of taller mass timber buildings.
AD: How have legal restrictions affected the development and implementation of tall mass timber buildings?
OF: The distinction of ‘combustible verses non-combustible construction’ has for the last 60 years or so restricted the development of mass timber technologies for the construction of taller structures. Don’t get me wrong, the distinction is very important. We want our buildings to be safe from the impact of a fire or a combination of serious events. However, new technologies, products and systems are available today that weren’t available or as well understood in the past. Scientific research and testing over the past 10 years and the construction of more than 15 tall mass timber buildings around the world has provided Authorities Having Jurisdiction (AHJ), building officials, designers, contractors and consumers confidence that these buildings are safe and we’re on the right track from a fire safety and performance perspective. Properly detailed and specified, as well as efficiently constructed, mass timber buildings provide a viable option to developers and consumers as our cities continue to evolve.
AD: Are there any limits to the height that mass timber buildings could go to?
OF: First, it is important to recognize that height is not the only objective of the competition or of the broader market potential of mass timber.
It’s not a matter of height, but what makes the most sense in size and scale for land-use and zoning and from a safety, cost, performance, occupant comfort, neighborhood and aesthetic perspective. We’re only beginning to understand what sustainable densification might mean and how it relates to mass timber design and construction. We understand we can’t continue building our cities as we have in the past. We now need to link the moving parts, variables and what makes sense. The tall wood prize competition is a first step. That said, it’s an exciting time for mass timber building design and construction, marked by impressive innovation, and so no one really knows what the limits to height might be.
AD: What is the goal of the competition in regards to promoting tall mass timber buildings?
OF: The clear goal of the competition is to identify and support proponents who can utilize new scientific information, develop technical expertise and incremental funding available through the Competition to safely design, specify and construct a tall mass timber projects of approximately 80 feet in height or taller in the U.S. that can effectively showcase the application, practicality and sustainability of innovative wood-based structural building solutions.
AD: What kind of proposals would you like to see in the Competition?
OF: The Competition funders would like to see proposals that can present a solid business case, and a viable wood-based structural system utilizing proven or innovative technologies within a well thought through integrated design with an efficiently presented construction methodology that is clearly supported by an AHJ.
For more information and to register, visit the competition's website.