Insulated metal panels (IMPs) are premier building products on the leading edge of innovation. The most commonly and widely utilized IMPs are formed by a continuously poured-in-place manufacturing process which binds interior and exterior steel facings to a polyisocyanurate foam core. They offer many advantages to building owners as well as those asked to erect insulated structures. IMPs are “green” products. They are a lightweight, cost-effective, thermally efficient alternative to other building practices such as tilt wall and masonry. They give a rigid feel and a sharp, in-place appearance. Offering tremendous flexibility to design professionals, the panels can be installed vertically or horizontally and in various finishes and different colors. IMPs are also offered in several different thicknesses, gauges and widths. IMPs service several market segments including the cold-storage industry, the commercial/industrial sector, institutional construction and the architectural arena.
Exceptional Insulating Properties
The most intriguing quality of IMPs is their exceptional insulating properties. Most panels offer a nominal R-8 per inch of foam. This translates into R-20 for a 2.5-in thick panel. The metal facings and rigid core yield a continuous insulation barrier with no loss of R-value at the attachment locations. In other words, the insulation is never compressed at a support. It is this tremendous insulating ability that translates into significant energy conservation and dollars saved.
Tested and Warranted
As with any quality building product, IMPs are rigorously tested and warranted. The panels are tested as a whole and as individual parts. The testing assures a building owner that the chosen product is safe and will perform to his expectation. A brief description of the general testing regimen is as follows:
Environmental Performance – IMPs are tested for air and water infiltration. Typical roof and wall side-laps allow zero water penetration and an almost immeasurable amount of air infiltration. The panels are also tested to specify their corresponding R-value.
Foam Core Characteristics – The insulating foam cores are structurally tested for shear, compressive properties, density, tensile strength and open cell content.
Fire Resistance – Chapter 26 of The International Building Code calls out the fire testing requirements for IMPs. The panels are tested for flame spread and smoke developed per ASTM E84. Factory Mutual also qualifies IMPs with their 4880 protocol which tests the panels in a room corner burn and a full scale burn test.
Engineering Properties – Most panels are classified by the FM 4881 and 4471 protocols. In addition, manufacturers will perform additional ASTM E1592 and E72 testing for their load tables.
Warranties – Industry standard warranties include a 2-year craftsmanship warranty to guard against manufacturing defects, a 20-year finish (paint) warranty and a 20-year substrate warranty, typically Galvalume® or galvanized.
Superior Spanning Capability
IMPs are strong and give a rigid feel and appearance. The bond of the steel facings to the insulating core produces a rigid composite section. It is not uncommon so see exterior wall spans in excess of 8’-0” and roof spans in excess of 7’-0”. Interior partitions often span from floor to ceiling with no additional means of support. As with any building product, a myriad of factors play into the design of these panels. A professional engineer should always reference the manufacturer’s load tables in order to dictate appropriate spans for the given project location.
Accelerated Installation Times
When compared to less rigid building components, IMPs require fewer structural supports. Fewer structural supports translate into fewer attachments, less labor and a reduced accessory cost. While lighter components and flexible insulations are greatly affected by windy conditions, IMPs are relatively uninhibited by less than ideal weather conditions. Specialized vacuum lift equipment is available to aid in the handling and installation of IMPs. This equipment allows for quick lifting and placement of panels and is offered for purchase or lease from several nationwide suppliers.
Though there are exceptions, the most common panel widths are 42-, 36- and 24-inch with 42-inch being the standard. The standard gauge metal thickness is 26-ga. with 24- and 22-ga. also available. Thicknesses typically range from 2 to 6 inches. Finishes are usually either embossed or smooth with options available for post-production applied finishes. Both roof and wall panels are offered allowing for a total building envelope application.
As demonstrated above, IMPs are indeed premier building products on the leading edge of innovation. They are a green product that saves energy. They are tested to resist the elements and the manufacturers stand behind their products. The panels are strong and lend themselves to quick, easy and efficient installation. The product offering is diverse allowing for a myriad of unique applications. Every day, designers seem to find new and exciting applications for this dynamic and versatile building product.