What building code does DC use? (2015 IBC, adopted editions)

Short answer. The District of Columbia is on the 2015 ICC family of codes with DC amendments — formally the DC Construction Codes (2017 supplement cycle, effective May 29, 2020). It is not the 2017 IBC and not the 2018 IBC. The electrical code is the 2014 NEC, and accessibility follows ICC A117.1-2009. The right basis line to cite on a memo, deficiency log, or inspection report is: "DC Construction Code (2015 IBC with DC amendments)."

Adopted editions by discipline

Each model code is adopted with a layer of DC amendments, so the governing text is the ICC base edition as modified by the District — not the unamended ICC book.

How to look up a section

Section numbers should be confirmed against the adopted text rather than recalled from memory, because a DC amendment may delete, substitute, or renumber a provision. Two authoritative sources:

1. The published DC code viewer, which overlays the DC amendments side-by-side with the 2015 ICC base text (and the sibling IMC/IPC/IFGC/IECC/IFC/NEC volumes).
2. The DC Department of Buildings amendment-supplement PDFs, which control when the viewer and the official text disagree.

Don't carry the DC basis across state lines

The adopted edition is jurisdiction-specific. Virginia (including Fairfax County) is on the 2021 VCC (2021 IBC base) with Virginia and county amendments — a different cycle entirely. Maryland uses the Maryland Building Performance Standards with county overlays. A code determination made under DC's 2015 basis does not transfer to a project in another jurisdiction.