Because this 352 square foot house is built in a hurricane zone they opted to build it using steel SIPs. This house was designed by David J. Bailey / Stephanie Harrison-Bailey. Metal panels are from Permatherm.
Photo courtesy of Jeremy Scott Photography
Most often identified with commercial structures, steel structural insulated panels (SIPs) have found their way into residential projects as well.
Most residential SIPs, are thick layers of rigid foam insulation that are bonded/sandwiched between two layers of structural material, such as plywood, oriented strand board (OSB), or metal. These panels are produced in a controlled environment and designed for individual projects. In addition to being used as structural exterior walls of the house, steel SIPs can be used for floors and roofs, as well as additions to the house and garages. For owners and builders, steel-skinned SIPs offer an exterior envelope that’s 15 times more air tight than traditional construction. They also provide a noise barrier, making them quieter than many other materials.
This steel SIP house is located in Dade City, Florida, which is one of the most common areas to find houses built with this material, since it is prone to hurricanes.
Photo courtesy of Chris Kavala.
Steel SIPs are highly energy efficient. Like most SIPs, steel ones create a high level of insulation, reducing the energy required to heat and cool the home. In most cases an energy recovery ventilator (ERV) or heat recovery ventilator (HRV) will be required to keep the air in the house fresh. Indoor air quality will also be better using steel SIPs due to the tighter and cleaner construction material used.
This southwestern style house was built using steel SIPs and is located in FL.
PHOTO COURTESY OF CHRIS KAVALAi
Steel SIPs are produced from a high level of recycled materials, so are environmentally friendly. The metal used is recycled material and can also be recycled at the end of it’s use. The rigid foam is composed of 98% air and non-CFC (Chlorofluorocarbons) blowing agents that are non-toxic and non-flammable. Most factories producing these panels recycle all of their waste materials.
Steel SIPs are available in longer lengths than ones made with OSB and are available up to 53 feet in length. In addition, the steel skin is the “vapor barrier” on walls so no additional covering is required before siding is applied. Like other SIPs, steel SIPs also go up fast, reducing construction time.
Built with Structall SIPs, this FL house was built on stilts to avoid flood damage.
Photo courtesy of Joe Dean
Because steel SIPs are lighter than traditional OSB panels they require no crane for installation. They are also termite, mold and rot resistant. Because Florida is often hit by hurricanes, building codes there require installation of steel hurricane straps in wood-framed construction. Steel-skinned SIPs essentially turn the entire panel into a hurricane strap, because of the strength of the metal versus wood panels. Joe Dean of Structall Building, says some of their homes are being engineered to withstand 150 plus mph winds with some additional fasteners or bracing to improve racking or shear characteristics up to 180 mph wind zones. He claims, that as local building codes in some areas become increasingly focused on energy-efficiency and strength, contractors and homeowners are abandoning traditional construction methods and looking to steel SIPs. Although manufacturers say they are being used throughout the country, they appear to be most prevalent in coastal areas where hurricanes are a big threat.
Steel SIPs were used for this Florida house built using Thermasteel panels.
Photo courtesy of Daniel Wensley
Panels can also be designed to meet the strict performance code in California’s seismic zone because of its capacity to resist lateral forces from earthquakes up to seismic zone “B”
Chris Kavala from PermaTherm SIPs projects steel SIPs to be a growing trend because of “labor shortages are creating a need for simpler building systems that can be assembled with unskilled labor .” He says they are slightly more expensive than stick framing, however labor is less and he says the “real beneficiary is the end user in energy savings.”