/ Field knowledge · IMC 306
The 30×30 has to be drawn, not hoped for.
IMC 306.1: you service the appliance without tearing out permanent construction, rated assemblies, or unrelated systems. A 30 in × 30 in level working space at the control/service side is the inspection gate — draw it.
Educational 2024 IMC 306. Confirm the adopted edition and the listing. This is not a clearance design for your unit.
What reviewers actually look for
- 306.1. Service without removing permanent construction. 30 in × 30 in level working space at the control/service side — dimensioned, not noted.
- 306.2 rooms. Door plus unobstructed passage 36 in wide × 80 in high (dwelling exception exists; it is not a free pass).
- Roof. Hatch/ladder and the walkway to each unit on the roof plan. A general note is a pre-occupancy hold.
- Removal path. The largest appliance has to come out. If the attic or closet cannot prove that, 306 is incomplete.
Lost to later coordination
Structure, ducts, piping, and electrical get placed after the unit footprint. The 30×30 disappears. Draw the box on M-101 before those trades fill it.
Source: DCT 306 Part 1 · roof: 306.5 · tool: access check.
What to send
Equipment location (room / attic / roof / above ceiling), architectural plans, and photos of the space as it sits today on a replacement.
If a tech cannot reach the unit without demolition
Send the location and the photos. Masterbuild will say whether 306 is a drawing dimension or a layout fight.
Send Project Background+1 (786) 398-6940 · osmany.portal@masterbuildconsulting.com
Masterbuild provides engineering services under a written scope. Nothing on this page is project-specific engineering advice, a code interpretation for your project, or a representation about permit approval.