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International Energy Conservation Code

Entire IECC document page (download copy available)
http://www.ecodes.biz/

Many states and municipalities have adopted portions of the IECC code as law.

* Code implementation depends upon the voluntary adoption of the code by local jurisdictions.

PURPOSE

The IECC was formed in order to establish energy-related standards for residential, multi-family, and commercial buildings. A major focus of the code provisions is on the building envelope insulation and window requirements, which vary depending on the regional climate. While the a large portion of the code deals with the U-factor and R-factor requirements, the code also addresses the heating, cooling, water-heating, electrical, and lighting systems of the building.

HISTORY

Prior to 1998 the IECC was known as the MEC, or Model Energy Code. The MEC was maintained by CABO (the Council of American Building Officials). CABO was comprised of three U.S. model code groups: BOCA (Building Officials and Code Administrators), ICBO (International Conference of Building Officials), and SBCCI (the Southern Building Code Congress International).

The three groups combined into an "umbrella" organization called the International Code Council, or ICC http://www.iccsafe.org/index.html. It was the ICC who issued the first IECC in 1998. Today both the IECC and the MEC are used, depending on what each state has adopted as their residential energy code. Both the U.S. Department of Housing and Urban Development (HUD) and the Rural Economic and Community Development (RECD) loan guarantee programs require compliance with the MEC regardless of state requirements.

COMMERCIAL BUILDINGS

The MEC and IECC codes for commercial buildings have changed significantly in the 2003 version of the IECC. Prior to the 2003 version the IECC only referred to ASHRAE/IESNA 90.1 standards in the area of lighting. However, chapter 7 of the 2003 IECC now states the following: "all commercial buildings shall meet the requirements of ASHRAE/IESNA 90.1."

RESIDENTIAL BUILDINGS

Specifying thermal envelope requirements for residential buildings (one, two, and multi-family buildings) is the main focus of the IECC.

With regards to lighting systems, the IECC 2003 uses ASHRAE/IESNA 90.1 standards as a base, but it also specifies acceptable housings on recessed lighting fixtures (section 502.1) as well as defining standards for interior and exterior lighting controls (section 805.2).

Recessed Can Lights
The IECC has certain requirements for can lights installed in the building envelope (see IECC Section 502.1.3). First, the can lights must either be Type IC rated or have a sealed box installed over the top of the fixture with at least 3 inches of clearance from insulation. The IC rating is visible on the inside of the installed can light. IC stands for "insulation contact," so an IC rating means the fixture is safe to be in contact with insulation. If a sealed box is used to meet the requirements, all electrical wire penetrations in the box should be sealed. In addition, the box should be sealed to the attic floor. Second, the can lights must be air tight to reduce air movement and associated energy loss. The fixtures must either pass the ASTM E 283 test for air leakage or must be manufactured with no penetrations between the inside of the recessed fixture ceiling cavity, and sealed or gasketed to prevent air leakage into the unconditioned space. A recessed can light installed inside a sealed box will also meet the requirements of the code. Look for labels on the fixtures that designate the fixtures as sealed or air tight.

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