Federal Building Codes - Residential

New Rule - Designs started on or after January 3, 2007

The current Federal code for low-rise residential building energy efficiency for which design for construction began on or after January 3, 2007 can be obtained in the Code of Federal Regulations in Title 10, Part 435, subpart A, sections 435.1 through 435.8.

The new rule requires that new Federal residential low-rise (3 stories or less above grade) buildings achieve an energy consumption level of at least 30% below those set by the 2004 International Energy Conservation Code (IECC), if cost effective. At an absolute minimum, the 2004 IECC must be complied with.

The Federal agencies procuring new housing are responsible for complying with this code, including determining levels of energy efficiency that can be achieved cost effectively.

Further information can be found in the Federal Register Notice announcing the new rule. See "Reference Resources" in page 4 of the PDF file in the notice.

Old Rule - Designs started before January 3, 2007

The Federal code for low-rise residential building energy efficiency for which design for construction began before January 3, 2007 can be obtained at the same link as for the new rule above but in sections 435.300 through 435.306 (Subpart C).

The requirements in the old Federal residential code are determined on a project-specific basis using software called COSTSAFR. Federal staff must run COSTSAFR to generate a project-specific point system that accounts for factors such as local fuel costs, climate, and construction costs for energy efficiency measures. The point system is completed by the building designer and contains options for energy efficiency measures such as insulation levels. The designer selects energy efficiency measures and obtains the points for these selections. The more points, the more energy efficient the design. A sufficient number of points must be obtained to achieve compliance with the code.

Designers can use the CAPS software or pencil and paper to complete the point system.

Note: COSTSAFR and CAPS are intended for use only in determining code compliance and do not give design guidance and feedback.

Contact Robert Lucas for more information.

Download COSTSAFR and CAPS (.EXE 508 KB)*

* Run the software .exe file after downloading to install the software.