At the height of Nevada’s population boom during the last decade, nearly 2,000 people per week, on average, moved to Las Vegas. The growth was comparable to adding a city the size of Green Bay, Wis., or Erie, Pa., to the metro area each year. Local governments were pressed to keep up with exploding infrastructure demands from roads to educational facilities. School district officials faced the particularly difficult challenge of building new schools quickly, yet under tight capital and operating budgets.
In the midst of the growth, the Clark County School District decided to build a replacement for the Jacob E. Manch Elementary School in the city’s northeast quadrant, near Nellis Air Force Base. The new 70,000-square-foot building would provide a school-within-a-school concept for 900 students, with individual buildings for various grade levels. It was required to be completed quickly to help reduce learning disruptions to students within the existing building.
Soon after the district awarded the design to SSA Architecture (Las Vegas), the project team determined that typical construction methods used in the region would not be feasible within the approved budget. At the time, construction costs in Las Vegas were increasing on the order of 1.5 percent per month.
The district also faced rapidly rising energy costs, with the challenge of heating and cooling schools during extreme temperatures. The outside air in the Las Vegas desert often tops 100 degrees Fahrenheit and remains high throughout the night in the non-winter seasons. As a result, buildings frequently do not have a chance to cool down naturally, placing high loads on HVAC systems for many hours of the day.
To reduce the construction schedule and provide for an energy-efficient building envelope, the designers chose structural insulated panels (SIPs) from Premier Building Systems (Fife, Wash.) in place of concrete masonry units or other exterior building shell materials. The result was a 60-percent reduction in the exterior framing schedule and a lowering of the HVAC operating costs by an estimated 65 to 70 percent.
Because the SIPs arrived at the job site in large, ready-to-install pieces, contractors were able to complete the building envelope in 47 days versus the 121 days originally scheduled for dry-in. During that time, they installed approximately 118,000 square feet of SIP walls and roofs (2,250 panels).
“The general contractor was shocked at how fast the panels installed; he said he’d never seen that size of schedule reduction,” said Gary Radzat, president of Shell Building Systems (Sebastopol, Calif.), SIP design and installation consultant for the Manch School.
An additional factor in speeding the construction is that the SIPs were manufactured with pre-cut electrical chases. This reduced the need to drill or modify the framing for installation of wires. The original labor plan estimated a need for 12 electrical workers, but the SIP construction helped reduce this to three, saving both time and money.
Altogether, using SIPs helped reduce the total project construction costs by approximately $2 million.
On the energy savings side, the SIPs helped create a tight, well-insulated building envelope with fewer thermal bridges than other construction methods ─ notably stick framing. The foam core provides a continuous insulation layer across each panel’s height, width, and depth, and there were fewer joints to be sealed.
“Using SIPs cuts down on energy-related costs two ways,” Radzat said. “There’s less demand for heating and cooling, so HVAC systems can be substantially smaller, saving on equipment costs. Plus, the ongoing costs to run the equipment are much less.” The HVAC operating costs are estimated to be as much as 65 to 70 percent less than other schools in the Las Vegas area. The HVAC’s lower cycling frequency also is anticipated to increase the equipment life by about 75 percent.
An ancillary benefit provided by the SIPs construction is a healthier indoor environment for students and teachers. SIPs help seal out dust and common pollutants, plus reduce interior noise in certain frequencies ─ an important factor given the nearby air force base.
As with other U.S. schools in a range of climates, SIPs helped the Manch School project team meet a range of competing construction and operating demands, while providing a code-approved building with long-term durability.
Joe Pasma, P.E., is the technical manager for Premier Building Systems, a firm that develops and manufactures high-performance, energy-efficient structural insulated panels. A licensed structural engineer, Pasma has worked with SIPs for almost two decades. For more information, call 800-275-7086 or visit http://www.pbssips.com/bc.