The following guide specifies illumination locations required by the 2021 IRC.

2021_IRC_Lighting_Guide

Residential attics and electrical panels both require permanent lighting in specific situations, but the governing details come primarily from NEC 210.70 and 110.26, with the IRC mostly silent except where an attic is made habitable or finished.

Attic lighting (residential)
For one- and two-family dwellings, NEC 210.70(A)(3) and 210.70(C) are the key sections.

Where an attic is used for storage or contains equipment requiring servicing (furnace, air handler, fan, etc.), at least one lighting outlet is required.

  • That lighting outlet must be switched at the usual point of entry to the space (wall switch or listed wall‑mounted control).
  • The lighting outlet must be located at or near the equipment requiring servicing when such equipment is present.

Finished or habitable attics are treated like other habitable rooms and require normal room lighting per 210.70(A)(1), not just a single service light.

From an IRC perspective, once an attic is considered a habitable attic it falls under the usual requirements for habitable space lighting, while the energy chapter (N1104 in 2021 IRC) drives high‑efficacy sources and controls for permanently installed fixtures.

Lighting at electrical panels
Illumination at electrical service equipment and panelboards follows NEC 110.26.

A working space must be maintained in front of service equipment, panelboards, and similar gear to allow safe operation and maintenance; the parent text of 110.26(A) requires that this space and access/egress be preserved even with doors open.
NEC 110.26(D) requires illumination of working spaces for service equipment, panelboards, and motor control centers; adequate lighting must be provided for this working area.

Lighting for the working space cannot be controlled solely by automatic means; there must be a manual means so the worker is not left in the dark by an occupancy sensor or similar control shutting off all light in the working space.

Headroom in the working space must be at least 6 ft 6 in (about 2.0 m), again to allow safe work in the illuminated zone.

Practical inspection notes

  • In a typical dwelling: expect a switched light in any attic that has storage decking or mechanical equipment, with the switch at the access and the luminaire near the equipment.
  • At panels: verify that the panel working space is reasonably well lit by a permanent or reliably available light source, and that an automatic‑only control does not shut off all light to that working space.
  • Always verify the edition of the NEC and IRC adopted by the local jurisdiction and any state or local amendments, as they can modify or supplement these base requirements.