For example, using ASHRAE 90.1-2013, climate zone 5a requires a roof U-value of.
This is based on the ASHRAE 90.1-2013 Standard the IECC 2015 code has, for the most part, the same values. If Semi-Heated is not allowed based on the heating system output, then each climate zone has major insulation requirement increases under the non-residential space.
Table 3.2, which is used to determine Semi-Heated Space, has not changed with the latest code updates. Semi-Heated Space: Space heated above 3.4btu’s/hr/ft2 and below 5 in climate zones (CL) 1 and 2, below 10 in CL 3, below 15 in CL 4 and 5, below 20 in CL 6 and 7 and below 25 in CL 8 (per ASHARE 90.1 2013) Non-Residential Space: Spaces heated or cooled above semi-heated requirement (per ASHRAE 90.1-2013). Remember these definitions:Ĭonditioned Space: Space that will be heated above 3.4btu’s/hr/ft2 and/or cooled (per IECC 2015). The only option that allows minimal insulation is Semi-Heated Space within ASHRAE 90.1-2013. The IECC 2015 and ASHRAE 90.1-2013 have the most stringent envelope requirements based on “Conditioned Space” and “ Non-Residential Space”. In previous versions of the IECC code and ASHRAE 90.1 Standard, it was easier to obtain lower insulation values in the roof and walls of metal buildings. There are some major changes to the envelope performance in the latest code cycle. In a long tab banded system, the purlins are exposed. Both options fulfill the metal building insulation requirements, so the system selected boils down to budget and preference.Īs you can see in the picture on the left, the purlins are covered by the fabric vapor retarder in a banded liner system. Long tab banded systems typically do not offer fall protection. Another key difference is that the OptiLiner ® banded liner system is an OSHA-compliant fall protection system. However, banded liner systems tend to achieve better U-values than long tab banded systems. Long tab banded systems are usually non-proprietary and meet the specifications of a filled cavity (FC) system.īoth systems provide High-R insulation to help meet stringent energy codes. Liner Systems (Ls) and Long Tab Banded Systems (FC): What’s the Difference?įirst, liner systems (Ls) such as OptiLiner ® are typically proprietary and, as you probably guessed, must meet ASHRAE’s requirements in order to be defined as a liner system.
Once that decision is made, the entire building envelope, including mechanicals and lighting, must follow the same path. The building designer will have to make the decision to pursue either IECC 2015 or ASHRAE 90.1-2013. The choices are the same for the rest of the envelope. If you haven’t used Liner Systems (Ls) or Filled Cavity/Long Tab Systems in the past, you will be required to start using them. This is a large jump, and many metal building contractors will feel the pressure.
Many states currently at the IECC 2009 code are bypassing IECC 2012 altogether and adopting IECC 2015. If your state’s current code is based on the older IECC 2009 and ASHRAE 90.1-2007 Standard, you will see more significant envelope changes. An Overview: IECC 2015 and ASHRAE 90.1-2013įirst, it’s important to know that I base the most recent code cycle changes on comparisons of the IECC 2012 code and the ASHRAE 90.1-2010 Standard.
That blog breaks down a lot of the background information pertinent to understanding the current code landscape, such as the difference between IECC and ASHRAE. Check the status of your state energy code at .Īlso, before you continue reading about the latest code cycle, you might want to revisit my primer on ensuring commercial code compliance in a post I wrote back in 2014. So, theoretically, your state could switch in the next few months or in a few years. Remember that each state is in a code cycle, which lasts two to three years. For some states the new code has already gone into effect as of January 1, 2017, but the exact timing of implementation depends on each state. The next commercial energy code cycle for most states is the IECC 2015 code and ASHRAE 90.1-2013 alternative path. The latest code cycle requires higher insulation values and an air barrier in the thermal envelope.