The Summit Office Park, named for its prominent location on a hill in Burlington, Massachusetts, needed a strong image to draw tenants to the five-story, 280,000-square-foot office, research and development facility. To accomplish that, designers chose architectural precast concrete panels in three distinct finishes. The choice proved especially beneficial when 2-foot overhangs were added onto the building as the design was being finalized.
Precast concrete panels were chosen for the project due to the versatility of the design, the economy of the materials, and the speed of erection, says Keith C. Calvin, project manager at Gutierrez Construction, the general contractor. The building features a V-shaped layout, with the two legs forming an interior angle where they meet at the main building’s front entrance.
The three precast finishes help to delineate the separate wings and reduce their scale. One wing was finished with a light, almost white concrete mix, while the other features a dark, charcoal mix. A medium-tan color was chosen for accents on both portions.
“The building is long and linear, and the changes in color help reduce the scale and break up the look of the façade,” says Calvin. A variety of samples and mockups were produced to achieve the proper combination. “We worked with our architect and precast contractor for some time to get the lighter color the right shade and to get the charcoal color dark enough to provide sufficient contrast.”
The biggest challenge came in creating the 2-foot overhangs that were added as the design was being finished. “The slab edge projected off the building about 2 feet from the columns, so the connections had to be about 2 feet long from the columns to the backs of the panels,” he says. “It was a big challenge, as the steel had to be able to handle the additional load, and we had to introduce a number of connections to secure the panels.”
In all, 233 precast concrete architectural panels and spandrels were cast, and the erection moved smoothly. It took approximately 42 days, finishing in August 2016. “Some of the areas of the site were tight to maneuver in, and it also has a grade change, but we had reasonably good weather and didn’t run into any mayor problems,” Calvin says. Being on top of a hill, erectors were conscious of high wind issues but by planning ahead were able mitigate the effects.
The result was a dramatic look for a prominent building. Occupancy is scheduled for the third quarter of 2017 after interior finishes are installed.