Interim Amendments to the 2020 National Electrical Code Show Changes are Premature

Codes and Standards
Published

Since the release of the 2020 National Electrical Code (NEC) in August 2019, Massachusetts, Colorado, Wyoming, and South Dakota have adopted the new building codes, with 18 additional states in the process of adoption.

Significant changes that impact the cost of construction of single-family and multifamily homes were included in the new edition, such as the requirement of receptacles serving 250-volt appliances to have GFCI protection, electrical service supplying dwelling units to have a surge-protective device, and the requirement of emergency disconnects accessible in an outdoor location for one and two-family dwellings.

But recent proposed amendments show that the early adoption of the 2020 NEC may have a detrimental impact on builders in states with the new requirements, as the code may change after certain conflicts were discovered.

The National Fire Protection Association (NFPA) has since released proposed Tentative Interim Amendments (TIA) to the Code Making Panel 2 Committee members for review and balloting. A TIA notes errors or omissions, addresses hazards, or identifies conflicts within the code that were overlooked during the regular revision process with the purpose of correcting the NFPA Standard through an amendment.

Of significance, there are three TIAs that could affect the home building industry:

  • TIA 1529 – Postpones the new GFCI requirement for air conditioner condenser units to address a conflict with potential tripping issues with certain types of ductless mini split equipment.
  • TIA 1535 – Revises language to clarify that stairway lighting dimming controls at one location cannot limit the maximum brightness of lighting controls at other levels.
  • TIA 1537 – Addresses a conflict with new code language that requires GFCI protection for branch circuits rated up to 250 volts. The Association of Home Appliance Manufacturers requested the requirement be postponed for 30- to 50-amp receptacles within six feet of a sink in order to allow product standards for cooking appliances connected to these outlets to be harmonized.

All TIAs are sent to the Code Making Panel committee members for balloting, but do not become official amendments to the NFPA standard until review by the NFPA Standards Council. Their next meeting is in December where they will review the ballot results for these items along with the committee comments and determine if each tentative amendment passes.

To find out if your state has adopted the 2020 NEC, or is in the process of adopting the latest edition of electrical codes, see the map published by the National Fire Protection Association.

NAHB has published the National Electrical Code Suggested Amendments and Code Adoption Kits for State and local HBA’s as consideration to maintain cost-effective and affordable code provisions.

For more information on the NEC and its adoption process, contact Daniel Buuck.

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