Green Codes for Low-Rise Residential Construction Up for Debate
While more than 1,200 codechange proposals were submitted for the 2012 International Green Construction Code, fewer than 600 were submitted for the 2015 IgCC. However, some of these proposals are challenging the code’s basic parameters.
Among them is the relationship between the 2015 IgCC and the International Code Council 700/National Association of Home Builders National Green Building Standard, ICC 700/NAHB NGBS. The scope of ICC 700/NAHB NGBS is the residential portion of any building that is not classified for institutional use. It addresses the building itself, as well as the building site and subdivisions, if applicable.
The scope of the 2012 IgCC, on the other hand, is all buildings and their sites. An exception is provided for single-family homes, duplexes and townhouses that are three stories or less in height, as well as residential care facilities and apartment buildings that are four stories or less in height. But the exception only applies if the adopting jurisdiction chooses ICC 700/NAHB NGBS instead of the IgCC for these types of buildings. If the adopting jurisdiction does not specifically make this choice, then the IgCC applies to all types of residential and commercial buildings.
Proposals to remove these provisions from the IgCC were under consideration at the ICC Group C Code Development Hearings in Memphis as this issue went to press. If these provisions are removed, then the scope of the IgCC will be limited to high-rise residential and commercial buildings, and will not address low-rise residential construction. In that case, the choice to adopt a green code or standard for low-rise residential construction will need to be separate from the adoption of the IgCC for commercial construction. If the provisions are retained and an adopting jurisdiction does not choose to use ICC 700/NAHB NGBS for low-rise residential construction, then the provisions of the IgCC will apply.
The latter would include IgCC provisions such as those under discussion at the current hearings. These include the status of Life Cycle Assessment and the various components that go into performing that type of analysis, prescriptive and performance design for energy efficiency, electives available to an adopting jurisdiction and to the building designer, dynamic glazing, shading devices on fenestration, automatic glare control of glazing, bird-impact reduction and the building envelope’s acoustical performance.
The code change committees that hear the proposals can vote to approve them as submitted, approve them as modified, or disapprove them. Interested parties are able to offer suggested floor modifications for the committee’s consideration. If an assembly action is called for after the committee votes, that motion will be tabled for one week. During that one-week time period, all registered members of the ICC will be able to vote on that action online. If the assembly action is successful, a public comment on the committee action will be automatically included on the agenda for the public comment hearings in the fall.