A 10,000-square-foot second story was added to a Massachusetts school by building a second-floor slab that was structurally isolated from the first floor, and using the slab as a work platform for the addition. 

JM Coull (JMC) was awarded a $12.6 million design-build contract to construct the addition and a new 33,000-square-foot fine arts center/gymnasium building for the Whitinsville Christian School (WCS) in Whitinsville, a village in the town of Northbridge. This effort required JMC workers to cut holes through the roof and slab of the institution's half-century-old campus building, thread steel columns through the holes onto newly constructed concrete footings, and build the new elevated second floor slab.

The contractor also constructed an enclosed, structural steel bridge connecting the second floor addition with the new building.  

JMC partnered with design firm Dixon Salo Architects of Worcester, Massachusetts, as well as acoustical consultant Acentech Studio A of Cambridge, Massachusetts, and theater design specialist Nextstage Design of New Haven, Connecticut. Team engineers included Johnson Structural Engineering, Neal Mitchell Associates, and Andrews Surveying and Engineering.

Pouring the Columns

According to Tom Roche, JMC's Project Superintendent, the challenging work for the second-floor addition began during the school's March 2016 spring break. At this time, crews cut holes through the existing floor slab and poured 11 new 2-foot, 6-inch deep concrete footings for columns that were to be installed later. The new footings were cast up to the bottom of the existing slab, covered with two layers of foam insulation then topped with enough concrete to be flush with the top of the existing floor slab. This procedure created temporary plugs with thin concrete covers that could be easily pierced and removed later to allow access to the new footings.

During the summer break, workers installed column base plates on the new footings and inserted tubular steel columns through holes cut in the existing roof and onto the footings. The existing roof structure stayed in place, with the structural steel frame for the second-story addition taking shape above, including the installation of permanent steel deck forms for the placement of a new lightweight concrete second-floor slab.   

Roche pointed out that, with the completion of the new floor slab, trades personnel were able to complete the second-story addition while working on a platform structurally isolated from first-floor classrooms.

Another challenging aspect for the contractor was the marked differences in elevations and types of soils across the site, requiring the importation of suitable fill for certain areas - about 16,000 cubic yards total - and the demolition and removal of several hundred cubic yards of ledge in other areas. Ledge was not blasted but instead was shattered by excavator-mounted hydraulic demolition hammers and exported from the site.        

As part of the contract, JMC relocated the school's playground to make way for the new building. The new steel-framed gym/theater facility houses a performing arts theater with a stage, seating, curtain system, lighting, and audiovisual systems, while the gym incorporates several basketball courts, scoreboards, bleachers, locker rooms, athletic equipment, a training room, and a multipurpose room. A lobby containing a trophy display case joins the two spaces. JMC's contract also includes a patio, ramp, handicap parking, a new road and sidewalks.

The enclosed bridge serves as a conduit between the theater and gymnasium, and ties into the new second-story addition above the existing pre-school. 

Established in 1924, the school began classes in the basement of a church in 1928, and subsequently constructed its main campus building in Whitinsville in 1968 and 1969. With about 600 students and 70 faculty and staff, WCS is accredited by the New England Association of Schools and Colleges, and is organized into a pre-school, elementary school (grades K-5), a middle school (grades 6-8) and a high school (grades 9-12). The school is located on a scenic 40-acre site in in the village of Whitinsville, which has been designated as a mill village of national historic significance to America's earliest industrialization by the John H. Chaffee Blackstone River Valley National Historic Corridor Commission.

According to Adam Meyer, Director of Advancement at WCS, the school raised funds for the current campus upgrade and expansion through a Rise Up and Build Campaign that to date has netted $18 million and led to the construction of the new Athletic Field House and Performing Arts Center. The school's new gym/theater facility was essentially completed by JMC in May 2017, about 14 months after groundbreaking, and has already featured a number of athletic, musical and theater events.

Award Winning Company

Led by Andrew Coull, President, JMC is a construction management, design-build, and general contracting firm specializing in new construction and renovations for the education, healthcare, institutional, and corporate/industrial markets. These encompass advanced technology, life sciences, manufacturing, and commercial/fit-up. Established in 1984, the company is headquartered in Maynard, Massachusetts, and performs work throughout New England.

The company received a National Safety Excellence Award for 2016 from the Associated Builders and Contractors (ABC).  In order to be eligible for this award, firms must first have achieved the 2016 ABC Safety Training Evaluation Process Award at the Diamond, Platinum, or Gold level. JMC was the first Massachusetts contractor to receive the ABC Diamond level safety award, which is the highest level attainable, and has qualified for the Diamond level every year for the past seven years. The company received the award during Workforce Week 2017, held in Fort Lauderdale, Florida by the national construction industry trade association, which represents more than 21,000 members from 70 Chapters.