SLI 47+7 located in Seattle’s University District is the first residential project built according to a new solution by Sustainable Living Innovation (SLI), a division of CollinsWoerman. SLI is selling their design and technology of fast-tracking construction of a multi-story building with a standard component-based building system. SLI’s patented technology is a pre-fabricated kit-of-parts which expedites a building’s sequential construction efficiently and economically.
This game-changing system is a result of more than six years of collaboration between DCI Engineers’ Mark D’Amato and Tom Xia, CollinsWoerman’s Arlan Collins and Dale Paul, and key players at SLI. DCI Engineers was responsible for the site planning of SLI’s 47+7 project which was under the direction of Associate Principal Darren Simpson. According to DCI’s Project Engineer Anish Talati, more A/E/C professionals will want to customize and construct high quality buildings this way because of the dramatic advantage behind component-based technology: shorter construction schedules. To accomplish this competitive edge, SLI entrusted DCI to make the components construction-friendly.
SLI’s goal is to make their component-based building design competitive with traditionally built wood frame buildings. This was done by pre-fabricating the floor systems, demising walls, utility walls and other components at an offsite, environmentally-controlled warehouse. All of these components have MEP parts already pre-installed to minimize the work required on the field. Meanwhile, the onsite construction crew focuses on work that can only be done at the project site (such as pouring concrete foundations and setting precast elevator cores). When the completed kit-of-parts is delivered to the site, the crew can quickly assemble and anchor the factory-built components. This minimized the need for onsite material storage or staging areas.
Exposed steel columns, beams and concentric braced frames formed the building’s exterior gravity and lateral systems. Designing simple and reliable connections for efficient installations was one of DCI’s biggest contributions to standardize SLI’s build process. All structural connections were designed using bolts so that no field welding was required.
The engineering team made additional recommendations to make SLI’s component-based design construction-friendly, marketable, and within feasible price points. The engineers developed the best solution and materials for the pre-fabricated floor slabs and roof framing systems. DCI helped develop the cold-form steel framing and exterior exposed steel frame for the building so its height can be beyond five stories (the height limit of wood-framed modular buildings).
Since August 2014, the engineering team has monitored the progression of the much anticipated six-story building in the University District. The residential mid-rise has a targeted six-month completion date. If a similar project was built in the traditional “core-and-shell-first” process, such a tight turnaround would be impossible. The fast-track schedule was achieved by pre-fabricating architectural and MEP components with the floor and wall assemblies, instead of sequentially installing each individual component by traditional construction methods.
Sellen Construction lifted and arranged all of the pre-fabricated wall and floor panels to complete one level in under five hours. When a layer of topping concrete was poured and dried for this level, the crew could start assembling the next floor. This process allowed the building to be topped off in December.
47+7 exemplifies how SLI’s component-based building system can grant developers or property owners the best of both worlds: quality living space and economical construction. Influencing the bottom line is a tangible solution in expediting buildings throughout the country, and possibly around the world. SLI has been approached by developers seriously considering the advantages of this new method of construction. For example, it’s very suitable for projects located in regions with longer winters and shorter construction seasons. Component-based design could also make market-rate housing options more accessible in denser metropolitan areas with limited affordable living spaces.
Check out SLI’s live cam for up-to-date images of the 47+7 construction progress. See SLI’s building solution for yourself, and determine if component-based building is the way of the future.
About the Author
Anish Talati, Associate | As an Associate, Anish enjoys being a member of the blog committee because it allows him to reach out to the world and share with them the work that DCI Engineers does. His favorite part about being an Associate at DCI is seeing a building take shape based on the ideas and collaboration of everyone involved in a project. When he is not at work, Anish enjoys volunteering his time for the betterment of the community.
Rose Bechtold, Communications Specialist | Rose comes from a journalism and technical writing background. She is in her element while in research mode and naturally immerses herself in expert knowledge by interviewing staff members about new subjects. In her spare time, Rose practices plein-air sketching of buildings and random scenes around town.