As Sun Microsystems describes itself, "We're the dot in .com." And as a leader in products and services for businesses on the World Wide Web, Sun Microsystems is a rapidly growing company with an increasing need for space. So in 1997, Sun broke ground on Phase 1 of a new, 73-acre corporate campus in Broomfield, CO, comprising of four office buildings and a food service building interconnected by a pedestrian walkway.
The two- and three-story buildings provide 563,130 sq ft of space to house approximately 2,000 administrative, research and development, service, and support personnel, who began occupying the areas of the new complex in June 1998. The first building of Phase 2, which will house an additional 1,000 employees, is currently under construction.
"Given the growth our business is anticipating, we needed a new central campus to consolidate all of our Colorado employees in one location and provide space for additional staff," explained Ray Monicelli, project manager for Sun Microsystems. "Our biggest challenge at the outset was establishing a construction program that would ensure that we met the goal of completing the first half-million square feet in under a year."
Merging Onto The Fast TrackWith time of the essence, Sun assembled a team with design-build experience, including Trautman & Shreve, Inc., the Denver mechanical contracting subsidiary of EMCOR Group, Inc. (Norwalk, CT), which was awarded the $18-million contract for the mechanical installation for the entire first phase of the project. Trautman & Shreve's contract for Phase 1, with construction manager-general contractor Swinerton & Walberg (Arvada, CO), encompassed all mechanical, hvac, plumbing, and controls work.
The Phase 1 mechanical systems included a three-cell, 5,000-gpm Evapco (Taneytown, MD) cooling tower, three 5-million-Btu Ajax (Santa Ana, CA) boilers, three 700-ton Carrier (Syracuse, NY) chillers, 26 Carrier air-handling units, and associated Paco (Brookshire, TX) pumps.
Designed by HOK (St. Louis), the buildings had phased completion dates based on the owner's desire to complete each area four weeks prior to its occupancy date. The first area of Phase 1 was scheduled for occupancy on June 4, 1998.
"This required completion of the central utility plant, campus loop piping and air handling systems, which make up the majority of the mechanical and plumbing systems, by May 8, 1998 - a mere nine and a half months from the start of mechanical systems construction," noted Dennis Gibson, project manager for Trautman & Shreve. "Pre-construction services allowed us to foresee problems and make changes to ensure that final documents represented the most efficient use of the owner's budget."
Based on schematic designs created by the mechanical engineer, Tao and Associates (St. Louis), Trautman & Shreve's CAD department engineered constructibility drawings with 3-D collision check, which allowed the contractor to fabricate and install the central piping plant in five weeks.
"Our involvement allowed us to anticipate design changes and proceed ahead of phased construction documents," Gibson pointed out.
Value engineering strategies saved the owner more than $1 million on the cost of the mechanical portion of Phase 1 without compromising the system's functionality.
"When you're involved in a fast-track project, cost issues are sometimes pushed aside by the pressure of the construction schedule," Gibson said. "But we were determined not to allow that to happen. We invested time in value engineering and, as a result, achieved the owner's aims cost-effectively."
A Muddy StartThe mechanical system design called for a central utility plant with piping systems distributing hot, chilled, and domestic water to the five buildings in a looped configuration through a crawl space no higher than 4 ft. The crawl space piping is 10-in. to 18-in. diameter steel piping stretching over 10,000 ft.
"As if the challenges posed by cramped quarters and large pipe-bore weren't enough, installers were knee-deep in mud from heavy rains," Gibson recalled. "Crouching, they had to maneuver the 40-ft sections of 18-in. pipe, weighing 2,800 lbs each, around the beams and girders, then hang and weld them into place."
Working with its supplier, PVC Specialties (Denver), Trautman & Shreve helped design and install a cost-effective thermal expansion system with specially designed anchors, guides, and expansion loops to give the crawl space more pipe flexibility during thermal expansion. The mechanical engineer's original drawings and thermal calculations were given to PVC, whose own engineers maximized the configuration of the devices to minimize the number needed, saving the owner approximately $250,000.
The team is applying the knowledge gained from Phase 1 to improve Phase 2. The expansive bentonite soil on the site expands in response to moisture, pushing upwards on the pipe hangers in the crawl spaces, so on Phase 2 the plans leave ample space for expansion.
Good Design, Better RevisionThe central utility plant comprises the three chillers, three boilers, and associated pumps and piping that supply water to the campus loop. The cooling tower 500 ft away is connected to the plant by two 500-ft pipe runs of 24-in. underground condenser water piping. A flexible connection system allows for pipe movement caused by expansive soils. To accommodate the schedule for Phase 1, the plant foundation, crawl space and structure, and equipment penthouses were all built before the equipment's arrival.
An open-air concrete pitting covered with grating was designed for a special rigging area, so equipment could be lowered by crane approximately 30 ft into the plant. The air-handling units were shipped in sections to fit through the structural steel in the roof of each penthouse.
Trautman & Shreve proposed redesigning each penthouse mechanical system to meet the cfm requirements while reducing the total number of units, and reducing their associated piping, ductwork, and controls by half.
"The original design called for four 20,000-cfm air-handling systems," Gibson explained. "We were able to combine two 20,000-cfm units into a single 40,000-cfm unit and, using the same manufacturer that manufactures the chiller, obtain a quantity buyout, saving the owner approximately $1 million on the package and increasing maintenance space in the penthouses."
Upward And OnwardThe first building under Phase 2 of the project is scheduled for completion in spring 2000. The new building requires an additional 700-ton Carrier chiller, an additional five-million-Btu Ajax boiler, four Temptrol air-handling units, and associated piping and ductwork. Also to be added is a 1,680-gpm, 700-ton Baltimore Aircoil Co. (Baltimore) cooling tower. Designed for extremely low temperature conditions, it will be used in winter for free cooling. Phase 2 provides for two additional buildings.
"Sun Microsystems left room for future growth in the plans," Monicelli said. "While we are certainly not on as fast track a schedule as in Phase 1, we're optimistic that we'll need the space relatively soon." ES