IBC Chapter 27 Proposal

This page expands upon a proposal submitted to the ICC on 8 January, 2024:

Performance-based electrical wiring design within buildings (10627)

The proposed text is bold underlined:

2703.1 General

Performance-based building premise wiring design for non-emergency feeder circuits.

2703.2

Feeder circuits identified in the National Electrical Code shall be permitted to be sized based on demonstrated load provided that sizing calculations are performed by a qualified person, as determined by the regulatory authority having jurisdiction.

2703.3

Demonstrated load. Historical maximum demand watt information recorded over at least a 24-month period for the same type of facility as the one in question, equated to watts per m2.

Reason:

We present this concept to the ICC community fully aware that it may be perceived as ‘outside ICC jurisdiction’ and will receive a smart rejection. Our intent is to raise awareness of an ongoing discussion that began at the University of Michigan as far back as 1999. Electrical professionals there observed that at least half of our building’s interior distribution transformers (numbering in the thousands across nearly 50 million square feet) were seldom loaded above 20 percent of their kVA rating throughout their lifecycle. The application of LED illumination and variable speed drives accelerated the downward trend.

We have authored multiple IEEE technical papers on this subject. We maintain collaboration with fellow design engineers (experts at NFPA and in the consulting industry) to narrow the gap between design load and observed load. More detail is found in the link below:

[Additional information: https://standardsmichigan.com/ibc-chapter-27-proposal/]

The proposed text is intended to be a placeholder. It closely mirrors the Canadian Electrical Code, which allows performance-based design discretion in sizing building interior power chains. By contrast, NEC wiring design is prescriptive, aligning with NFPA’s primary mission of advancing fire safety.

Oversized power chains contribute to waste in customer-owned transformers, service panels, enclosure metal, architectural space for service rooms and switchgear, ventilation systems, sheet metal in ceiling plenums, air flow motors, illumination, egress entrance design, and more.

NFPA’s own electrical experts acknowledge this issue. Despite research projects sponsored by its Research Foundation to inform technical committee members, proposals to reduce material and energy waste are routinely rejected by ‘vertical incumbents’—manufacturers, testing labs, insurance, inspection entities— who benefit economically from oversized building power chains.

In summary, while NFPA has been supportive and respectful of user interests (building owners), the link provided presents more significant technical substantiation, and is respectful of the balance NFPA must maintain with other constituencies .

This proposal, at the very least, aims to broaden awareness of this obvious cost-saving opportunity. We want to find a home for it in any of the dominant standards catalogs that inform safe and sustainable building construction (e,g, ICC, NFPA, ASHRAE, IEEE, NECA, NEMA, etc.)

This will reduce construction cost. Modification and relocation of the concept will be gratefully received.

We look forward to reading a way forward in the committee’s response.

Related Research: (oldest to newest)

IEEE:

Rightsizing electrical power systems in large commercial facilities

The safety and economic benefit of reduced power design densities permitted in the 2014 National Electrical Code

Rightsizing Commercial Electrical Power Systems: Review of a New Exception in NEC Section 220.12

Evaluation of Electrical Feeder and Branch Circuit Loading: Phase 1

NFPA:

Evaluation of Electrical Feeder and Branch Circuit Loading: Phase 1

Electric Circuit Data Collection: An Analysis of Health Care Facilities

Mazetti: