A sustainable component for walls and roofs that is finding increasing popularity among architects and builders is the insulated metal panel, or IMP. At its most basic, an IMP is simply some form of insulation sandwiched between facings of sheet metal, assembled in a factory or shop setting.
However, when one considers the many types and thicknesses of insulation available, and the variety of metals, alloys, thicknesses, colors, finishes, panel sizes, shapes, profiles, and configurations offered by different manufacturers, IMPs offer virtually endless design possibilities. It is no wonder then that IMPs are cropping up on schools, factories, office buildings, prisons, airports, warehouses, hotels, office buildings and retail facilities worldwide.
IMPs offer the architect wide design latitude, by virtue of the many manufacturers and products available in most markets. IMPs also offer the builder relative speed and simplicity of construction, by virtue of their shop-fabricated, unitized and modular nature.
The panels can provide good energy performance, coupled with ready interior and exterior finishes and durability. Panel coatings typically resist corrosion, chemical action, chipping, chalking, fading, dirt accumulation, and can usually be easily washed and maintained.
While panels are typically supplied with moderately durable interior and exterior finishes that will wear well over time, higher-performance finishes may be selected for coastal or marine environments, industrial process plants, cold storage warehouses, and other special uses. Tongue-and-groove or keyway edge designs insure the ready assembly of panel walls and roofs, and panel systems include all necessary clip angles, fasteners, and trims to attach to structure and provide complete enclosure. Formed edges, ribs and varied facing profiles add stiffness and rigidity to the finished panels.
It is the all-in-one nature of IMPs that contributes so greatly to their success and widespread use. The panels typically provide enclosure + insulation + tight thermal seal + thermal break + vapor barrier + interior finish + exterior finish + interior light reflectivity + some exterior self-cleaning + speed of construction + minimal additional structure or framing + design + color.
IMPs are typically fabricated with face panels of either galvanized or galvalume (galvanized with a proprietary and highly durable zinc-aluminum coating) sheet steel, in gauges ranging from 26 to 22, though stainless steel may sometimes be used for interior panel faces subjected to chemical stressors. Cores of panels are usually comprised of either polyurethane or polyisocyanurate foam. Facings and insulating cores vary from manufacturer to manufacturer. Panel sizes range from a few feet to 5 feet or more in width, and up to 40 or 50 feet in maximum panel length.
So-called ‘architectural’ panels, customized to embody curves, configured edges or ribbed or embossed patterns for design effect, may be no more than about 3 feet x 12 feet in size. Such panels work well in curtain wall systems for office buildings and schools. Though almost exclusively used for exterior applications, where their performance characteristics can shine, IMPs can also be employed for interior partitions.