INFLATION REDUCTION ACT

Even more significant, the U.S. Inflation Reduction Act (IRA) of 2022 is offering significant incentives to help drive energy-efficient improvements in projects. The IRA modifies the tax incentive under section 179D of the Internal Revenue Code for energy-efficient improvements to existing commercial buildings, in addition to new construction, with increased deduction limits and other changes. In lieu of a one-time $1.88 per square foot tax reduction cap under the previous program, building owners can qualify for a reduction of up to $5 per square foot and can apply for the credit every three years.

To qualify, the improvement measures must enable the facility to use 25% less energy than a comparable building. With a 25% reduction, this means that the upgrade will yield a 50 cent per square foot deduction, scaling up to a $1 per square foot deduction for a 50% efficiency gain. The deduction then increases on a sliding scale by $0.10 for each additional 1% improvement up to a maximum of $5 per square foot.

Energy savings, measured as an EUI reduction, are based on a measurement of the building’s actual energy use over the course of 12 months before and after the energy upgrade. Applying this opportunity to roofing upgrades, ICF International released a study in 2021 entitled “Life-Cycle Benefits of Energy Code-Compliant Roof Replacement.”²⁶ The study found that upgrading a typical existing low-slope roof to a code-compliant roof can result in significant whole-building energy savings.

Further, a roof improvement project could increase the 179D deduction in a range of $0.20 to $1.10 per square foot depending on the building type and climate zone, with an average increase would be $0.60 per square foot. In colder climates, and for building types with large roof-to-floor ratios like schools and large retail, savings will be even greater. Consequently, roofing upgrades are highly recommended for owners and architects looking to cash in on IRA tax reduction benefits.

Photo courtesy of Nucor Insulated Panel Group

After a fire damaged the Wurstfest festival venue in Braunfels, Texas, the event organizers were in a hurry to rebuild in time for the annual festival. IMPs were chosen for their speed to construction and enhanced structural performance.

RETROFITTING WITH IMPS

In addition to the many noted benefits IMPs for new construction, the panels are a great choice for building enclosure upgrades. “IMP assemblies are increasingly popular for deep energy retrofits, additions, and recladding projects, especially in the northeast climate zone,” states Jason Jewhurst, FAIA, partner and principal, Bruner/Cott Architects, Brookline, Mass.

IMPs can be installed over many types of backup walls including wood, steel, concrete, and masonry. And the system’s ease of installation reduces costs schedules and labor costs. As noted, IMPs are fire resistant, and overcladding boosts acoustic performance as well.

In addition to presenting a fresh, updated facade, perhaps the biggest benefit is the boost in thermal savings. And thanks to IMP’s all-in-one water, vapor, and air barrier, those performance savings are locked in. Also of note, the IMP's air and water seal is located on the interior side of the panel and in the panel joinery. This design allows it to be completely concealed and not visible to the exterior.

“Leveraging high performance, time-tested materials like IMPs for building retrofit is just a natural extension of the same value these materials have proven over decades of successful application,” states Drake. “Few alternatives offer such lightweight, long-span, single-source applicability as IMPs, and their long history with integrated glazing, flashing, and design options further offer solutions that can increase the aesthetic results while extending buildings’ productive lifespans.” For IMP roofing retrofits in particular, while the new roof is highly thermally efficient, re-roofs can also capitalize on the roof’s existing insulation.

As noted, the building stays dry and weather-resistant during installation, and workers are afforded an existing work surface as opposed to the open purlins and joists with new roof construction. In addition, the through-fastened metal roof system diaphragm remains in place thereby preserving the original structural diaphragm strength used to design the original structure.

When re-roofing with an IMP, as opposed to completely removing the existing roof structure, building teams have the option of preserving the structure by adding a sub-framing system. These sub-purlins are structural members, typically 10 to 12 feet in length, made from 16 gauge, 0.060-inch-minimum 50 KSI structural grade G-90 galvanized steel and notched to fit over the ribs of the existing metal roof panels.

Factory notching provides a “structure to structure” connection with the least possible increase in assembly height. The system also adds strength to the existing roof system thereby offsetting the added weight of the new metal-over-metal roof components. These sub-purlins can be fabricated for almost any existing metal roof panel profile including screw-down, standing seams, and custom heights to accommodate added insulation between the old and new roofs. Some products offer an “anti-rotational” arm to stabilize the framing system that is attached over compressible insulation materials.

54 MIDDLESEX

Bringing a worn-out-looking 1970s office building back to life in Bedford, Mass., Bruner/Cott Architects designed a hybrid assembly of insulated metal panels (IMP) and high-performance ribbon curtainwall windows. Similar to existing buildings of this vintage, the project’s design capacities required that the recladding be heavier than the original veneer brick facade. However, a new masonry façade would have cost twice as much as metal. “The combination of high thermal performance per square foot of façade, low weight per square foot, competitive cost of fabrication, and installation made IMPs a strong candidate for a project of this scale and budget,” reports Jason Jewhurst, FAIA, Partner, Principal, Bruner/Cott Architects, Brookline, Mass. “Insulated metal panels allowed us to pull it all together and provide the updated aesthetic the owner was seeking in an energy-saving system,” added Michael Frechette, AIA, then a project architect with the project’s contractor Dacon Corporation.

Photos courtesy of Nucor Insulated Panel Group

In all, 16,000 square feet of grey and white 3-inch IMPs, in 24-inch and 36-inch widths, were installed. The selected panels have a 22-gauge exterior skin and a 26-gauge interior skin. The horizontal IMPs were installed in widths consistent with windows and other design elements of the building.“It’s a lot more difficult to do a horizontal renovation than a new vertical installation,” related Dave McGrath, a sales engineer with the Mansfield, Mass.-based Controlled Environment Structures (CES), whose firm installed the facade, “We had to line up our seams with the mullions on the storefront windows. There is a lot of custom fieldwork because we weren’t working off a blueprint; these are field conditions.” For example, the original concrete masonry unit presented a very rough surface, and the aesthetic was not desired for the new facade. To rectify this, CES came up with a clever solution to attach the IMPs to a sub-framing system, fully concealing the CMUs.

In addition, a continuous bracing clip had to be installed prior to the panel installation to provide lateral bracing. “The bays of the building are 28 feet across and required intermittent lateral bracing between the structural columns,” explains Frechette. “The system was fabricated such that it could be lifted into place by a crane and mechanically anchored from inside the building, making it very easy for workers to safely and efficiently install the panels once arrived at the site.“ He adds that the system had to be detailed to accommodate imperfections in the existing cast-in-place structure. This informed how the panel joints and expansion joints would allow for a degree of adjustability during the site installation.

Another challenge was working with panels and their smooth finish. Because any imperfection is exposed, the quality of manufacturing with the IMPs had to be right on. Fortunately, it was. “The smooth finish adds to the crisp geometry the owner wanted,” Frechette says. “It is a clean aesthetic and an upgrade from the typical embossed finish.” Ultimately, the project team was amazed at the level of thermal efficiency that the IMPs deliver.

“The energy efficiency of the metal panels is a decrease of two-thirds the amount lost through the walls and the savings is something like 70 cents a square foot over 40,000 square feet, reports Dacon Senior Project Manager Jeff Prince. “We had heard that it was going to be beneficial, but it really wasn’t until the tangible savings that we saw on our energy costs for managing and maintaining the building that it really became apparent,” echoed Ian Curran, Director of Leasing, Curran Management, the building owner.