Zoning › State preemptions › District of Columbia

DC Inclusionary Zoning — mandatory citywide IZ (ZR 2016 Subtitle C Ch. 10) (DC)

Tracked preemption from the District of Columbia overlay bundle.

Overview

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Effective
2006-03-14
Sunset
—
Authority
district
Scope
state:DC
Other District of Columbia preemptions
NCPC Submission Guidelines — tightened federal review staging (in force 2026-01-08)New York Avenue (NYE) text/map amendments — fixed 8% IZ set-asideComprehensive Plan Amendment Act of 2021 — District Elements + NCPC Federal ElementsDC Inclusionary Zoning Plus — deeper affordability overlayZR 2016 — Zoning Regulations of 2016 (11 DCMR)DC Home Rule Act of 1973 — Congressional review & §602(a) reserved mattersNCPC — federal review of DC projects affecting federal interestDC Zoning Enabling Act — Zoning Commission jurisdiction and federal-appointee structure
Primary-source summary
Local zoning (ZR 2016) can set heights **at or below** the Height Act ceiling. In much of downtown, ZR 2016 matter-of-right height is at or near the federal cap — meaning the federal statute is the binding constraint, not local zoning. Outside downtown, local zoning is typically more restrictive and the Height Act is not binding on the parcel.

Trigger predicate

When this evaluates true for a parcel, the law's preempted fields take precedence over base zoning.

AND
  • parcel.iz_zone_applicable == True
  • OR
    • project.unit_count ≥ 10
    • project.residential_gfa_sf ≥ 10000

Preempted fields

5 fields on the base district schema are rewritten when the trigger fires.

FieldOpValueNote
inclusionary_set_aside_pctfloor_at88% set-aside for steel/concrete construction
inclusionary_set_aside_pctfloor_at1010% set-aside for wood/light-frame construction
affordability_tier_mfioverride60Rental: typically 60% MFI
affordability_tier_mfioverride80For-sale: typically 80% MFI
density_bonus_far_pctfloor_at20IZ projects entitled to up to 20% additional FAR / density bonus, matter-of-right in most IZ zones

Citation

Authority source
Inclusionary Zoning Implementation Amendment Act of 2006, DC Law 16-275; DC Code §6-1041.01 et seq.; 11 DCMR Subtitle C, Chapter 10
§ DC Code §6-1041.01 et seq.; 11 DCMR-C §§1000–1099
https://code.dccouncil.gov/us/dc/council/laws/16-275

Research notes

One of the strongest mandatory IZ programs in the country. Applies to new multifamily of ≥10 units or ≥10,000 sf residential GFA in IZ zones, and to substantial rehabs meeting thresholds. Administered by DC Department of Housing and Community Development (DHCD). No local opt-out — every qualifying project must comply. Closest state analog is California's Density Bonus Law, but DC's regime is fully centralized rather than municipal+state.