In 2015, the International Energy Conservation Code (IECC) made a new change regarding the thermal resistance requirements for duct insulations in unconditioned spaces. Specifically, the code called for ducts in unconditioned spaces in climate zones 5-8 to be insulated with R-12 insulation.1 (Please see the complete code for all details and any exceptions.) In terms of insulation, designers can expect that the higher the R-value, the greater the insulating power of the insulation.
Climate zones 5-8 are in the middle to northern part of the country, and they often experience much colder weather patterns than zones 1-4. As a result, ducts in unconditioned spaces in climate zones 5-8 have typically required much more energy to maintain consistent temperatures. The IECC introduced the R-12 code change in an effort to address the inefficiencies of these types of duct systems in these regions.
The primary problem with this change, however, is that there hasn’t been any single layer, flexible R-12 duct insulations available on the market. This can make it challenging for contractors to both source the appropriate materials and install them efficiently. Recognizing this, Johns Manville developed a robust portfolio of R-12 rigid and flexible duct insulations, specifically for applications with requirements like those described in the 2015 IECC. We’ve outlined the details and thermal performance characteristics of each of our R-12 duct insulations below.
Microlite FSK Formaldehyde-free™ duct wrap is our newest addition to the R-12 duct insulation family, and it is the only duct wrap on the market with an installed R-value of R-12 in a single layer. Microlite FSK duct wrap comes with an FSK (foil scrim craft) facing, designed to help ensure a closed system that prevents moisture drive and offers condensation control. This design helps prevent damage to the insulation and surrounding areas. Additionally, the material is GREENGUARD® Gold certified. It is the only duct wrap available that offers installed R-12 performance in a single layer.
Linacoustic RC is the only flexible duct liner to offer R-12 performance in a single layer. This 3” liner comes with an antimicrobial coating, Permacote®, that helps protect the product and reinforces the glass mat to help provide a smooth airstream surface. Additionally, the edges of Linacoustic RC are coated with Permacote. The coated glass mat surface offers superior resistance to the penetration of incidental water into the fiberglass wool core. Despite the increased thickness, the material is still easy to cut using a water jet cutter or a Rotozip® machine.
Linacoustic R-300 is a rigid fiberglass board used to line ducts that also offers R-12 insulating performance. As with Linacoustic RC, the airstream surface of Linacoustic R-300 is coated with Permacote to help protect the product and the airstream surface.
XSPECT ISOfoam APF Board is a polyisocyanurate board designed to be used outside the building envelope. It delivers R-12 insulating performance in just 2 inches, making it an ideal material for rooftop duct applications. The lightweight material has a foil facer on both sides and is easy to fabricate on the jobsite. Additionally, the closed cell foam is moisture-resistant making it a robust solution for outdoor applications. When properly installed, XSPECT ISOfoam creates a closed system that prevents vapor drive and helps protect the ducts.
Fiberglass Board: 800 Series Spin-Glas® (made to order)
800 Series Spin-Glas is a rigid fiberglass board insulation for ducts and equipment that can be made to order in thicknesses and densities that offer R-12 thermal ratings. The material is offered with three different facings: plain, AP (all purpose), or FSK. 800 Series Spin-Glas is used outside ducts to offer both thermal control and condensation control (when faced).
The thermal conductivities of 800 Series Spin-Glas vary depending on the thickness and density of the product. Contact us for more information on the appropriate density and thickness for your application.
Need more information?
As we continue to evolve our product lines to better meet the needs of the market, ground-breaking materials like our R-12 duct insulation portfolio will help installers maximize their efforts and optimize their processes. For more information on JM’s R-12 duct insulation portfolio, please contact us at 800-654-3103 or click here.