›› Retrofit Team DESIGNER: EXTECH Design/ Build, Pittsburgh, www. extechinc.com ENERGY ANALYSIS: Hesnor Engineering Associates PLLC, Adams, Mass., www.hesnor.com SKYLIGHT INSTALLERS: Richard Dembski Co., Home- stead, Pa., (412) 464-0415, and W.S.Nielsen Co. Inc., Alpharetta, Ga., www.wsnielsen.com ROOFING CONTRACTOR: D J Wooliver & Sons, Lanesboro, Mass., (413) 442-0192
›› Materials
›› The Retrofit With completion of a major renovation, Shelburne Green office park takes on a dramatic new appearance. The previous structure was a “smorgasbord of attached buildings,” according to Dan Cameron of DHCameron Construction Co. The original 15,000-square-foot building was construct- ed in the 1950s and then added onto over the years with pre-engineered buildings. Insulated metal panels were used to tie the buildings together. Now offering nearly 40,000 square feet of Class A office space, the office park provides a unique, comfort- able setting for a wide range of businesses.
A new 0.060-inch-thick clear-anodized aluminum standing-seam metal roof was installed, along with cel- lular polycarbonate structured sheet skylights, which were cold formed in the field to the curvature of the existing barrel vaults. All exposed fasteners were 300 Series stainless steel.
›› The Retrofit This modern-looking building was built in the 1960s and features a long aluminum-skinned barrel vault roof. The skylights and roofing in the barrel vault had leaked for years. The barrel-vault skylights were composed of two layers of thick, monolithic polycarbonate held together with gaskets that were not suitable for use with polycarbonate. The construction team removed the upper aluminum framing portions of the existing skylights, glazing material and gasket- ing. The inner portions of the skylight framing were structurally sound and, after an engineering review, were deemed to be sufficiently strong to accept the weight of the new system, as well as wind and snow loads. The new system features waterproofing based on extruded aluminum framing with low-friction- coated gaskets and continuous sheets of 25- and 16-millimeter cellular polycarbonate panels. By using these long panels, all horizontal joints were eliminated, minimizing the possibility of leaks. The framing also includes plastic spacers that serve as thermal breaks.
›› The Retrofit SubTropolis was created through the mining of a 270-million-year- old limestone deposit. In the mining process, limestone is removed by the room and pillar method, leaving 25-foot square pillars that are on 65-foot centers and 40-feet apart. The pillars’ even spacing, concrete flooring and 16-foot-high, smooth ceilings made build-to-suit facilities time and cost-efficient for tenants. A tenant requiring 10,000 to 1 million square feet can be in the space within 150 days. SubTropolis is complete- ly dry and brightly lit with miles of wide, paved streets accessed at street level. In addition, the underground location reduces a tenant’s energy consumption by 50 to 70 percent. Today, about 50 businesses with 1,500 employees transact business from SubTropolis, but the office park still has about 5 million square feet of leasable space.