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The Ocial Journal of the National Insulation Association FEBRUARY 2016 History of the metal building industry p. 8 Choose the right insulation for metal buildings p. 12 Code compliance what you need to know p. 18 Stop air leakage with air barriers p. 26 Prevent thermal bridging with thermal blocks p. 32 As seen in 2 Understanding and complying with todays evolving energy codes and standards presents unique chal- lenges for architects designers and builders of pre- engineered metal buildings. As the new energy codes and standards the Inter- national Energy Conservation Code IECC 2012 and 2015 and ASHRAE 90.1-2010 and 2013 are being adopted across the country specifiers are find- ing that conventional single and double layer fiber glass insulation systems may no longer be able to meet the thermal performance requirements specified for metal building roofs and walls. In an effort to navigate and hopefully simplify energy code compliance the intent of this article is to help specifiers determine code adoption status using web-based tools and to review various high R-Value Low U-Factor insulation systems currently available for metal building roofs and walls that provide code compliant options. Code Adoption Status Many states and municipalities have adopted recent versions of either the IECC or ASHRAE 90.1 stan- dard or drafted their own energy codes.The Depart- ment of Energy DOE has summarized the current status of energy codes and standards adoption across the United States in the map below. This map is available at Additional information relating to code adoptions can be found using the Energy Code Navigator at By Hal Robbins Navigating February2016 3 Energy Code Compliance for Metal Buildings httplamtec.comenergy-code-navigator this tool was created to help specifiers navigate the code-adoption process in a few simple steps as listed and shown below. Step 1 Enter the zip code for the project. The State and Climate Zone are then provided. Step 2 Select the applicable code from the drop- down list. If this is not known a link is provided that will take the user to the DOE website where this can be determined. Once the code is selected a table will display showing prescriptive assembly R-Values and U-Factors as well as alternate systems shown in the table as Compliance Options. The Com- pliance Options will provide equivalent or better thermal performance than the prescriptive solu- tion see table below. Note There are provi- sions in the codes to allow for the use of these alternate non-prescribed Compliance Options to be used as long as the thermal performance can be demonstrated by a thermal test report or finite element analysis FEA model. This documentation is typically available from the insulation suppliers. Insulation System Options Once the applicable U-Factors have been deter- mined for the project the specifier must select an insulation system that best meets the needs of the project. In some cases this is the prescriptive option however in many cases a better performing insulation system is necessary to compensate for a lower per- forming component of the buildings envelope. 4 When trade-offs or substitutions are required the energy code compliance of the buildings envelope can be verified using COMcheck a free program available from the DOE at comcheck. Non-prescribed systems can be entered into COMcheck using the Other U-Factor Option and then the Metal Building Roof drop-down as shown below As guidance the following is a review of new High R-ValueLow U-Factor insulation systems currently available for metal building roofs and walls. Roof Insulation High R-Valuelow U-Factor metal building roof insulation systems can be broken down into 2 generic categories filled cavity fiber glass and rigid continu- ous foam insulation. Filled Cavity OptionsU-Factors of 0.037 or Less Filled cavity options with U-Factors or 0.037 or less include Long Tab Banded LTB system. Liner system. Both the LTB and liner systems fill the cavity between the purlins with fiber glass insulation. A minimum of 2 layers are used one layer is installed between and parallel to the purlins and one layer on top of and perpendicular to the purlins. In both cases the insulation is supported by a series of bands attached to the underside of the purlins. From a thermal performance standpoint both systems perform comparably. Contrary to some of the claims being made in the marketplace actual side- by-side thermal testing by an independent accredited laboratory has demonstrated comparable performance with both the LTB and liner systems. ASTM C1363 test results for 2 LTB and liner assemblies using 2 different insulation levels are shown in Table 1. These results demonstrate that the filled cavity LTB system and the liner system performed comparably in this side-by-side test program. Due to the inherent variability in this type of testing the slight difference seen should not be considered to be significant. The primary differences between these 2 systems relate to the orientation of the vapor retarder facings With the LTB system the vapor retarder is laminated to the lower fiber glass layer and the facing tabs follow along and over the purlins where they are sealed together to maintain the continuity of the vapor retarder. With the LTB system the lower purlin flanges are exposed which allows for unobstructed instal- 5 February2016 Table 1 ASTM C1363 Test Results Long Tab Banded System Liner System R-19 R-118 purlins 0.037 0.039 R-25 R-1910 purlins 0.029 0.028 lation of mechanical and electrical equipment. With the liner system the vapor retarder is installed separately from the insulation under the purlins and above the banding. With a liner the purlins are covered so they are not visible within the building. If a liner is being used it will be necessary to cut into the vapor retarder to gain access to the structural components of the building. When selecting an insulation system for a metal building roof the following factors should be considered Does insulation system meet the required U-factor Does the insulation system provide a smooth attractive installed appearance Do the facility operators need to have easy access to the purlins What is the installed cost and long-term performance Rigid Continuous Insulation Continuous insulation is defined in the 2015 IECC and ASHRAE 90.1-2013 as follows IECC-2015 Continuous Insulation Insulating material that is continuous across all structural members without thermal bridges other than fasteners and service openings. It is installed on the interior or exterior or is integral to any opaque surface of the building envelope. ASHRAE 90.1-2013 Continuous Insulation Insulation that is uncompressed and continuous across all structural members without thermal bridges other than fasteners and service openings. It is installed on the interior or exterior or is integral to any opaque surface of the building envelope. Continuous insulation provides a strong durable and attractive interior finish. It is often a preferred option for use in applications where high interior humidity is present such as indoor swimming pools and nurseries. Continuous insulation is also commonly used in applications requiring a low interior temperature such as cold storage buildings. In some cases hybrid systems utilizing a combination of foam and fiber glass can be used to achieve required thermal performance. When considered these systems should be reviewed with your insulation fastener and building supplier to avoid any unintended consequences such as condensation or structural issues. When choosing continuous insulation it is advisable to confirm that the fire ratings of the products are acceptable for use by the local fire codes. Depending upon the fire rating a separate thermal barrier may be required by code. Wall Insulation High R-Valuelow U-Factor metal building wall insulation systems can also be broken down into 2 generic categories filled cavity systems fiber glass and rigid continuous insulation foam. Filled Cavity Systems with U-Factors of 0.059 or Less Several single and double layer fiber glass filled cavity insulation systems have been developed to meet the Metal Building Wallrequirements established in 2015 IECC and ASHRAE 90.1-2013.These systems include 6 By Je P. Fox Insulating metal buildings is not as simple as it once was. Do you follow ASHRAE 90.1-2010 IECC-2012 IECC-2009 or the new IECC-2015 Attempting to navigate the complex world of code compliance can provide somewhat of a challenge. There are 2 key dierences between ASHRAE 90.1-2010 and IECC-2012 regarding the building envelope and building insulation. Only ASHRAE 90.1 has a specic designation for a building that is unconditioned and only semi-heated. Semi-heated unconditioned buildings will meet the energy code with a single layer system in the roof and walls based on ASHRAE 90.1-2010. It is also important to keep in mind that state codes will override local city codesunless the local code is more stringent in which case it must be used. In addition to the code compliance tools listed above NIAs metal building laminator members can be a valuable resource. For guidance from a NIA laminator in your state visit membership. NIAs online membership directory can be used to search for insulation laminators contractors distributor fabricators and manufacturers by specialty and location. Code Busters Single-layer systems that use a combination of fiber glass to fill the cavity between the girts and foam tape between the wall panels and girts. Double-layer systems that are essentially the single layer system detailed above with a second layer of fiber glass installed between the outer girt flanges and the wall panels for added thermal performance. Depending upon the U-factors required foam tape or 1 foam thermal blocks are also used. With these double layer systems U-factors as low as 0.036 can be achieved. Rigid Continuous Insulation As detailed previously for the roof system continuous foam insulation is preferred for high-temperature high-humidity applications. The same advantages and caveats discussed for the roof also apply to the walls. Conclusions New web-based tools have been introduced to help architects designers and builders navigate the adoption status of state energy codes and provide guidance on the insulation system options available for code compliance. A variety of new high R-Valuelow U-Factor insulation systems have been developed for metal building roofs and walls that meet the thermal requirements specified in the current energy codes and standards. While these new systems may not currently be listed in the Appendix Tables of the ASHRAE 90.1 Standard provisions in the codes allow for alternate systems to be used as long as supporting thermal performance documentation is provided. When considering the insulation system options available for your application it is important to consult with your insula- tion supplier or contractor. They will be able to provide guidance on thermal performance installation and cost.To learn more about options for reaching out to compliance experts in your area see the sidebar Code Busters. The author has previously published on this topic and portions of this article may have been reprinted from the September 2015 issue of Metal Construction News tinyurl. comztce6u8. Hal Robbins has a degree in Chemistry from Radford University. Previously he worked at CertainTeeds Insulation Group from 1981 to 1994 in Product Development with a focus on Facings Adhesives Coatings and Fire Testing. Mr. Robbins has been the Technical Director for Lamtec Corporation lamtec.comabout-lamtec since 1994 and is actively involved with ASHRAE and ASTM. He can be reached at LAMTEC products are proudly manufactured in the USA. Specify Long Tab Banded LTB Filled Cavity Insulation Systems with Lamtec Vapor Retarders Architects Specifiers Contractors and Building Owners use LTB systems with Lamtec Vapor Retarders because LTB tested modeled assemblies satisfy prescribed U-Values in 2015 IECC and ASHRAE 90.1-2013 Cost effective way to meet or exceed prescribed U-Values for Metal Building Roofs Easier access to the purlins for installation maintenance of electrical HVAC and sprinkler systems Attractive bright white appearance Lamtec is the most specified name for insulation vapor retarders Long Tab Banded systems results All tests modeling were performed on standing seam roof assemblies. Results based on Finite Element Analysis Modeling Hot Box Tests Finite Element Analysis Modeling and Installation Instructions can be found at LAMTEC.COM. Contact your insulation supplier for more details ASSEMBLY DESCRIPTIONS U-VALUE R19 Faced R11 Unfaced 0.037 R25 Faced R11 Unfaced 0.035 R25 Faced R19 Unfaced 0.029 DOWNLOAD ARCHITECTS GUIDE or CONTRACTORS GUIDE Filled Cavity Systems for Metal Buildings at LAMTEC.COM Roof Panel Thermal Block Fiberglass Over the Purlins Faced Fiberglass Between the Purlins PurlinLamtec Facing Banding This article originally appeared in the February 2016 issue of Insulation Outlook published by the National Insulation Association Reston VA. Copyright 2016 NIA. Reprinted with permission. Contact NIA at 703-464-6422 or NIA is a not-for-prot trade association representing both the merit open shop and union contractors distributors laminators fabricators and manufacturers that provide thermal insulation insulation accessories and components to the commercial mechanical and industrial markets throughout the nation. Since 1953 the northern Virginiabased association has been the voice of the insulation industry and is dedicated to keeping the commercial and industrial insulation industry up to date on the latest industry trends and technologies. For more information contact NIA. National Insulation Association 12100 Sunset Hills Rd. Suite 330 Reston VA 20190 703-464-6422