Tecta Solar installs a rooftop PV system on a Massachusetts facility

355 Main St., a distribution warehouse in Whitinsville, Mass., boasts the recent installation of a 1,869 kilowatts-peak rooftop photovoltaic (PV) system, which at the time of its installation was the largest rooftop PV system installed in Massachusetts and the third largest system of any type in Massachusetts.

Two-thirds of the roof already had been reroofed by others&emdash;using various EPDM roof systems&emdash;when Tecta America was asked to reroof the remaining portion to install a rooftop PV system.

“The client wanted a turnkey developer that could provide engineering, procurement and construction of a new roof, complete with a new 2-Megawatt (DC) rooftop solar PV power plant,” says Brett Chapman, sales director for Tecta America.

Installation

Tecta America New England, North Billerica, Mass., reroofed the remaining 687 squares of the roof. The existing roof was an aggregate-surfaced built-up roof (BUR) system on a wood deck with no insulation. The other existing roofs were less than a few years old and in good condition.

Tear-off was not needed on the remaining BUR system, which the company reroofed.

“A new mechanically attached Firestone Building Products reinforced black EPDM roof system, including one layer of Firestone 1 1/2-inch-thick ISO 95+, was installed over the existing vacuumed built-up roof,” says Andrew Shinner, general manager for Tecta America New England. “On the other four roof elevations, the roofs were inspected, roof seams were probed and minor repairs were completed. About 16,000 linear feet of seams were stripped in to ensure long-term reliability of the existing roof assembly.”

Tecta Solar then installed the rooftop PV system, which features 8,307 SunTech 225-watt polycrystalline modules and a ballasted Sunlink racking solution tilted at 5-degrees.

Materials were hoisted to the roof using cranes and/or forklifts or lulls.

Safety precautions were enforced during the project for the Tecta America crews and all subcontractors.

“A nonpenetrating Garlock Railguard 200 safety rail system was the primary safety system used during the project and was installed around the perimeter of the roof to eliminate fall hazards,” Shinner says.

Although the project largely did not take longer than expected, the solar production was delayed slightly because of ice and snow.

Working together

The companies faced various challenges during the project.

“The most difficult challenge with any roofing and solar project is the weather, protection of the roof, and the safe coordination and installation of specialized solar equipment,” says Patrick Bollinger, construction manager for Tecta Solar. “The second biggest challenge to any large commercial rooftop solar project is the scheduling and coordination of the project to meet a precise construction schedule. Finally, design changes can add additional unforeseen challenges. In the case of this roof, the racking system took some additional effort to accommodate a large gas line running diagonally across the middle roof elevations.”

The coordination of the project required the cooperation of various people.

“One of the unique aspects of this project was the coordination between our master electrician and work force, as well as the diverse group of supporting subcontractors&emdash;from our concrete subcontractor to our medium voltage electrician to Internet and communications vendors and manufacturers to our inverter and monitoring commissioning technicians,” Bollinger says.

Bollinger says he is happy with the project.

“For me, the most rewarding part of this project is that even though many of the same general solar components are used in each solar PV system, each component still is engineered and selected to meet specific building and electrical requirements,” Bollinger says. “Designing, planning, coordinating and assembling cutting-edge solar PV systems is, I think, the greatest reward.”

Roofing Contractor: Tecta Solar and Tecta America New England,
Manufacturer: Firestone Building Projects and Suntech
Color of EPDM: Black
Type of Attachment: Mechanically attached
Location of Project: Whitinsville, Mass
Type of Building: Warehouse

Text of the project profile is copied from original source.