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The 2015 International Energy Conservation Code (IECC) regulates minimum energy conservation requirements for new buildings. Understanding the way different components and materials interact in a building can reduce problems with moisture, indoor air quality and ice dams. An energy efficient building may also result in lower energy bills.
The following are some of the specific code requirements of the 2015 IECC related to residential construction. Please refer to the code to reference all applicable requirements including additional requirements for commercial construction.
Insulation- The IECC outlines the following general insulation requirements: Ceilings – R49 (R-38 may be permissible if it extends uncompressed over the wall top plate at the eaves); Walls – R20; Floors – R30. Please refer to manufacturer’s information to verify the R-value of blown insulation and spray foams.
Energy Efficiency Certificate- This
is completed by the builder or design professional and lists the energy characteristics and efficiencies of the building materials and systems. The Permits Office can provide a copy of this certificate that must be permanently posted on or near the electrical distribution panel.
Blower Door Test- A building’s thermal envelope (such as the exterior walls, floor & roof that enclose conditioned space) must be constructed to limit air leakage. A blower door test is required in order to verify that the building has an air leakage rate not exceeding three air changes per hour. A copy of the test results must be submitted to the Permits Office.
Duct Testing- Ducts located outside the building thermal envelope must be pressure tested to determine air leakage. A copy of the test results must be submitted to the Permits Office.
Mechanical Ventilation- As construction practices reduce air leakage in homes there is a greater need to control indoor air quality. Mechanical air ventilation systems are now required. These systems provide a controllable and consistent supply of outdoor air for improved indoor air quality and occupant comfort. These systems can dilute indoor contaminants, such as formaldehyde, cleaning agents, odors, and allergens and help control relative humidity and moisture. Building inspections will verify proper mechanical ventilation.
Manual J & Manual S- Manuals J & S are protocols developed by the Air Conditioning Contractors of America (ACCA) to help properly size HVAC equipment. Oversized furnaces and air conditioners may cost more, waste energy, and sometimes provide lower levels of comfort. Manual J consists of load calculations that accurately determine a home’s heating and cooling needs. Manual S is then used to select the properly sized heating and cooling equipment based on Manual J load calculations. In new homes with a forced air heating system, a copy of the Manual S & J calculations must be submitted to the Permits office.
Please call the Permits Office at 301-334-7470 for more information.