IRC 2009 Code Brings Changes in How Homes Will Be Built
Decisions voted on at the International Code Council (IRC) Final Action Hearings in mid-September will result in a number of changes in how homes are built in communities where the model 2009 International Residential Code is adopted.
The most controversial change is the new mandate for fire sprinkler systems in one- and two-family homes. (For an earlier story in Nation’s Building News, click here.) The language mandating these systems was previously located in the appendix of the code as appropriate language for jurisdictions that wanted to adopt a requirement for sprinklers.
Under the 2009 IRC, jurisdictions will have to choose not to adopt residential fire code provisions. However, they can expect to face a well-funded coalition of system manufacturers and installers who will work hard to keep the mandate. During last month’s hearings in Minneapolis, local building code officials largely sided with home builders to oppose the sprinkler requirements, citing technical concerns and their added, unjustified expense.
Beyond the sprinkler issue, single- and multifamily builders can expect to see changes in many other areas. Among them:
- Carbon monoxide alarms. A new provision requires the installation of carbon monoxide detectors outside all sleeping areas, with the number required varying by the configuration of the space.
The detectors usually cost between $50 and $75 apiece, but a bigger concern is their reliability, NAHB testified at the code hearings. The units have only a five-year life span before they need to be replaced; even when new, the detectors have a high incidence of false alarms or false positives — resulting in unnecessary calls from the fire department or, more ominously, giving home owners a false sense of security.
- Wall Bracing Requirements. The new code increases the amount of wall bracing needed to resist wind loads for three-story homes, homes with large open plans and homes in high-wind regions. In addition, the new code requires blocking between the roof framing members at braced wall panels for homes with deep truss members or roof joists, or homes in high-wind and high-seismic areas. The new requirements include prescriptive blocking details for these conditions.
The new code will require uplift straps at braced wall panels for many homes, even in low-wind regions. In addition to adding cost, these changes may require revisions to some stock plans or changes to standard detailing practices — not only to bracing, but to blocking requirements and strapping. The blocking requirements may also complicate insulation and attic ventilation practices.
- Wall and Roof Cladding Inspections. For multifamily builders, the new International Building Code will require wall and roof cladding inspections in high-wind regions. While this may seem sensible in light of the damage that has been observed in hurricanes, the requirement itself is vague and does not specify what elements of the wall and roof cladding system need to be inspected.
This could lead to building departments requiring in-plant inspections for shop-fabricated elements of wall and roof cladding systems, even if those elements are pre-tested and labeled for high-wind resistance and even if the fabricating shop is hundreds of miles from the job site.
- Domestic Clothes Dryer Ducts. NAHB is already working with proponents of this code change, which would require a product available from only one manufacturer and also limit the length of the ducts to 25 feet. The proponents have indicated that the length was proposed in error.
- Shower Liner Test. Building inspectors will now be required to observe whether the liners under showers can hold 2 inches of water for 15 minutes without any leaks. NAHB objected to the requirement, complaining that it would unnecessarily complicate the home inspection process. Immediate leaking should be evident without a water test, NAHB said, and the test will not detect slow leaks that appear later.
- IFC Construction and Design Provisions. A new requirement in the International Fire Code makes fire code officials responsible for inspecting construction outside the home, in addition to inside the home. The change was opposed by NAHB and building code officials, who noted that fire officials are charged with fire prevention, not construction, and do not necessarily have the background to conduct an appropriate inspection.
- IECC Code Changes. In previous versions of the International Energy Conservation Code, home builders were permitted to make so-called “equipment trade-offs” when using the performance path — such as substituting a high-efficiency furnace for additional insulation or more expensive windows. The change eliminates that option for home builders, requiring them to make changes in the building envelope to meet code.
Multifamily builders will also see changes in glazing requirements under the IECC. Each unit will only be allowed a maxiumum of 15% glazing, down from 18%.
The U.S. Department of Energy has said that homes constructed under the 2009 IECC will save at least 15% to 20% more energy than homes built under the 2006 version of the code. A summary of the code process on the agency’s Web site praises NAHB and energy conservation groups for technical assistance in preparing the code proposals.
For more information, e-mail Calli Schmidt at NAHB, or call her at 800-368-5242 x8132.
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