Concerns over volatile energy prices are encouraging facility executives to look for ways to improve the energy efficiency of their facilities. For many, that means looking past the building envelope to focus on energy-using systems. Even when the envelope is considered, most of the attention is focused on the roof. Other parts of the building envelope such as windows and exterior walls rarely get much consideration beyond maintenance or replacement needs.
Three overlooked technologies can improve the efficiency of the building envelope: insulated metal wall panels, exterior insulation and finish systems (EIFS), and interior insulating windows. Though none of the systems are new to buildings, design changes have made them more effective tools in reducing energy use while controlling construction and operating costs.
Insulated Metal Wall Panels
Once limited to industrial facilities, prefabricated insulated metal wall panels are gaining greater acceptance in commercial and institutional applications. One reason is that today’s panels are available in a range of colors and SIP finishes, offering aesthetic choices.
Panels are available in both structural and non-structural configurations, although most wall applications use structural panels. Panel thicknesses range from 3.5 to 9 inches, with widths ranging from 18 inches up to four feet. Panels typically come in 8-foot lengths, but are available in lengths of up to 32 feet for special applications. A class 1 polyurethane foam core helps the panels meet the fire safety requirements of the major model building codes. Most panels are constructed with a 20 gauge, galvanized steel exterior surface, though some are available with a wood exterior surface.
Panels are designed to attach directly to the building’s supporting structure. This one-piece construction and easy attachment of the wall panels speeds construction by eliminating the many steps used to construct conventional exterior walls.
With no breaks in the insulation, panels provide superior insulating properties over the entire area of the exterior wall. And unlike many exterior-wall insulating materials, the R-value of the foam core does not significantly deteriorate with time. The panels also have good acoustical properties.
Insulated metal wall panels also can be easily recycled. Panels can be readily removed from an existing facility during renovation or an expansion, moved, and then reinstalled.
It is also easy to remove and reinstall structural insulated metal panels. That is valuable in such applications as exterior walls of mechanical equipment rooms, where they provide facility staff much easier access than allowed by conventional built-up walls when removing and installing large pieces of mechanical or electrical equipment.