"Title 24" is the 24th title in the California Code of Regulations (CCR) which lays out the energy efficiency standards of both commercial and residential building codes, for the State of California. While in some circles Title 24 is synonymous with energy conservation, however, Title 24 actually pertains to all structural, mechanical, electrical, and plumbing systems, and has required measures for energy conservation, green design, construction and maintenance, fire and life safety, and accessibility. While largely based on the International Building Code, The California Building Code (Part 2 of Title 24) has additional amendments, made by the state, that must also be followed.
Even more specifically, Part 2.5 deals with the residential requirements. Some of those, requirements for the building envelope and for HVAC systems, are enumerated below.
1. Fenestration - Windows, glazed doors, skylights and tubular daylight devices must meet minimum insulation and air leakage standards.
2. Building Envelope - Air infiltration and/or leakage standards that apply to joints, cracks in and around windows, doorways, plumbing penetrations, openings for gas lines, attic access, etc...
3. HVAC - Equipment sizing, air distribution systems, duct installation, thermostats and zonal control.
All three of these refer to a houses ability to keep the conditioned air inside the building, prevent unwanted air from gaining access, and doing so in the most efficient way possible. Verification of the building envelope and of the HVAC installation can be done using one or both types of air infiltration testing equipment.
Duct Blasters or DucTesters - used for pressure testing the duct systems to check for leakage. Current standards dictate that the duct system should leak less than 5%. Some figures pegged the national average over 25% - a 20% reduction would make for SIGNIFICANT savings.
Blower Door Systems - large fans inside adjustable frames, built to fill open doorways, are used to depressurize the entire house allowing you to literally observe air infiltrating a home near plumbing penetrations, outlets, and framing for doors and windows.
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