Shiver Me Timbers! Fire, Boats & Really Big Trusses
Shiver Me Timbers! Fire, Boats & Really Big Trusses
Around 1:50 p.m. on June 20, 2012, a spark from a welder’s work fell upon a pile of dry wood and started a four-alarm fire that caused significant damage to the historic bulk work of Pier 29 in San Francisco’s waterfront district. The timing couldn’t have been worse, as the fire destroyed the roof and a large portion of the façade of the building, which was to be the home of the 2013 America’s Cup competition. The City of San Francisco was contractually obligated to provide the building for the race, and suddenly found itself in its own race against time to rebuild the structure in a few short months.
In order to pull it off, the city had to appease many different interests, from historical preservationists to community activists to race organizers; re-engineer the building structure based on practically hundred-year-old drawings and schematics; and do so in an impossible timeframe. Enter Eric Lincoln and Building Products Plus Company, based in Houston, TX, a leading producer of large-scale timber trusses and beams. In the end, they were the only company capable and willing to commit to not only design the trusses, but also manufacture and deliver them on time.
To truly appreciate the momentous task Lincoln and his team accomplished, we’re going to have to back up and explore the unique challenge Pier 29 posed, the many constraints facing the project, and, finally, the process of engineering, manufacturing and installing the 70-foot roof trusses needed for the project.
Pier 29 Hosts the America’s Cup
Pier 29 is one of the 18 pier buildings on the waterfront that are within the San Francisco Embarcadero Historic District, which includes the famous Fisherman’s Wharf, and is listed in the National Register of Historic Places. Pier 29 was built in 1915 by the State Board of Harbor Commissioners, and extends 800 feet into the San Francisco Bay with a 164,000 square foot pier shed. The pier was likely built as part of a competition between the cities of San Francisco and New York to construct the world’s preeminent commercial port system.
The bulkhead portion of Pier 29 fronting on The Embarcadero roadway was built in 1918 in the neoclassical architectural style in an effort to add aesthetic beauty to what was largely a heavily industrial waterfront. The structure of the bulkhead featured 70-foot wood roof trusses, creating an impressively large open pavilion at the entry to the pier shed. It was this history and grandeur that likely led the America’s Cup organizers to choose Pier 29 to serve as their base of operations.
At the time of the fire, the building did not have any tenants, and work was underway to begin preparing the building to host the 34th America’s Cup yacht race. Fire investigators concluded the blaze caused $2.4 million in damage, though the destruction was primarily limited to a relatively small portion of the overall pier building.
One of the America’s Cup key organizers, Larry Ellison, a co-founder and CEO of Oracle Corporation made it clear to the City of San Francisco that it was in their best interest (not to mention they were contractually obligated) to ensure Pier 29 would be repaired and ready when the race series officially begins July 4, 2013. While America’s third-wealthiest person (whose current personal worth exceeds $41 billion) is used to getting his way, he also raised a very good point. The America’s Cup is expected to create 8,000 jobs in San Francisco and bring in more than $1.4 billion into the region’s economy. With an anticipated 5 million total spectators—with 500,000 on “peak” days—there was a great deal of pressure to successfully rebuild Pier 29.
Pressure Cooker
Recognizing that time was not on their side, on July 10, 2012, the City and County of San Francisco’s Board of Supervisors passed a resolution declaring a state-of-emergency regarding Pier 29, which allowed the city to approve emergency contracts entered into by the Port of San Francisco. The resolution further directed the Port of San Francisco to take “all necessary and appropriate measures to perform repair work to Pier 29 in the most expeditious manner.” In essence, it did away with lengthy bid processes and gave the port the authority to get the work done as quickly as possible.
While the city wrangled through the politics, the insurer of the building quietly began putting out feelers to find subcontractors who could accomplish the work. They contacted Lincoln at Building Products Plus. “They said they were looking for someone who could engineer and build these 70-foot trusses quickly,” Lincoln recalled. “Because the building was on this Historic Register, they wanted the trusses to look as close to the originals as they could get.” Lincoln said he thought they could do it, so when the bid documents were put together, Building Products Plus was listed as a possible candidate for supplying the roof trusses.
Turner Construction was hired as the general contractor (GC) in early September, only three short months after the fire. Turner subcontracted the roof trusses to Bellcore Engineering, Inc. “One of the biggest challenges we faced was that we were trying to copy the design and assembly of a hundred-year-old building,” said Ken Burg, the Project Manager for Bellcore on Pier 29. “The city engineers couldn’t get the trusses to work, primarily because of the changes to load requirements between then and now.”
While putting together the initial bid package, Burg contacted their lumber suppliers to see who they would recommend to provide the trusses. He also contacted Lincoln, based on the insurance company’s recommendation, “In the end, we had several bidders say they could accomplish the job, but Building Products Plus was the only one who said they could engineer, design, manufacture and deliver the trusses within the necessary timeframe.”
That timeframe ended up being a little less than two months. Within that time, Lincoln and his team had to design each truss and then coordinate communication between Bellcore, Turner, the Port of San Francisco, and the insurance company, to ensure the plans met the needs and requirements of each group. “One of the most significant requirements we had in accepting the contract was that the city had to agree to turn around and approve any drawings we sent them within 48 hours,” said Lincoln. “Without that stipulation, this project could never have been completed so quickly.”
Design, Manufacturing & Delivery—Oh, My!
In total, Building Product Plus had to design six different truss layouts and manufacture 15 trusses. “We had to do all the engineering, and supply drawings and design calculations, including hand calculations for each joint,” said Chris Newhouse, P.E., Vice President of Engineering, SCA Consulting Engineers and the lead designer on the project for Building Products Plus. “All we had to start with were the spans and loads, along with architectural drawings the city supplied. We certainly had a lot of room to be creative. There were a number of things that we were able to do to simplify the retrofit of the building, one of these being a redesign of the truss-to-truss connection required to support and transfer the considerable loads.”
Eight of the trusses were 70-feet long with a top chord pitch so slight, it rose no more than two feet over the entire length of the truss. “The most challenging truss was the 58-foot, parallel chord girder truss, which carried the load of several other trusses,” said Newhouse. “The reaction loads on the truss at the bearing points averaged 22,000 pounds, so we ended up having to clad the top and bottom chords with a solid piece of half-inch steel that had to be cut into three lengths for shipping and then welded back together and affixed to the truss chords at the jobsite.”
Manufacturing these enormous trusses (some weighed in excess of 10,000 pounds) was not without its logistical challenges. “We had to create all the timber used in the trusses ourselves,” said Lincoln. “Most of it was 38-foot 10x10s and 10x12s that needed to be No. 1 and kiln dried to 19 percent.” In other words, when the contract was signed, the trees used in the project were still growing in a forest. Building Products Plus had to identify the trees they needed, have them harvested and delivered, and then cut and dry them. “The drying was one of the most difficult parts, getting that low of moisture on such large timbers without splitting them was a challenge.”
Beyond producing the timbers, they also had to find a third-party to inspect and grade each board. “Fortunately, we were able to locate an independent grader through Timber Products Inspection to come into our plant and grade each board,” said Lincoln.
Time was constantly a factor. They had to produce the lumber before some of the trusses were even designed. Further, they had to begin production on some of the trusses before the drawings were completely approved. “Fortunately, we never had a case where we had to rebuild a truss because of changes to the drawings,” said Newhouse.
Once the trusses were built, they had to be loaded onto trucks and hauled from Houston to San Francisco. “We’ve manufactured 89-foot trusses before, but these were a particular challenge because they had to stay under cover to maintain the moisture content,” said Lincoln.
The entire job was delivered in three separate truck loads. Loading each trailer took the better part of a day. “We had to back the trailer in and out in order to have enough room to lift and manipulate each truss, as it was stored in our facility, in order to load it onto the trailer,” explained Lincoln. Of course, after all the work that went into constructing each truss, there was the constant pressure to avoid handling the truss wrong, bending the truss too much or damaging the wood fiber in any way.
Hauling these massive trusses presented its own challenges. The trusses required a significant number of oversized load permits, and each load needed to be delivered before 4:00 a.m. The Embarcadero is one of the busiest streets in San Francisco, and with Pier 29 right up on the street, each truck load would have to block the road during delivery. “Delivery was one of the most significant logistical challenges,” said Burg. “Each truck arrived exactly when we needed it to, but that was just the first hurdle. We then had to crane each truss up and install them in a few short hours before rush hour started.”
Complicating matters was a temporary fabric roof that was installed over the building shell to allow workers to repair and construct the inside of the building long before the roof trusses arrived. This meant that each truss had to be lifted into place from inside the building. “We only had a few feet of clearance between the fabric roof and where these trusses needed to be placed. There were several times when I thought there was no way it was going to work, but the crane operator stuck with it and made it work,” said Burg.
Pieces in a Puzzle
“This job would have been a challenge regardless,” said Burg. “However, the tight timeline required everything to fit together perfectly like pieces in a puzzle.” It was a project that required every party involved to do their job efficiently and flawlessly.
“I can’t say there weren’t a few minor hiccups along the way, but, in the end, it was an immensely satisfying project to complete,” said Lincoln. “The best part is that we made money on the project.” Now that’s a storybook ending.
