Zoning › District of Columbia › District of Columbia County › Washington

Washington, DC Zoning

Euclidean-zoning. 11 districts · 7 overlays · 3 applicable state preemptions.

Overview

Code type
euclidean
Naming convention
letter-code

DC ZR16 uses letter-prefix plus hyphenated number sequences. R districts are detached/semi-detached residential (R-1-A through R-3), RF = residential flats/rowhouses, RA = apartment, MU = mixed-use, NMU = neighborhood mixed-use, D = downtown, PDR = production/distribution/repair, Special Purpose per Subtitle K. Numbers within a family are sequential intensity index — R-1-A is largest/least dense, R-3 is smallest/densest. NOT inverse-named; higher number = higher density (standard convention).

Worth knowing
  • DC is a federal district — state preemption framework does not apply. Federal constraints (Height Act, Home Rule Act, NCPC review) documented in federal_overlay_framework and state_preemptions_applicable as functional equivalents.
  • Height Act (1910, federal) caps all building heights city-wide; ZR16 zone heights are subservient. On most residential streets, the Height Act residence street cap (80/85 ft ceiling/parapet, further limited by street width minus 10 ft) is more restrictive than the RA zone height allowances for RA-4/RA-5.
  • ZR16 reorganized in August 2023 — reintroduced base-zone-plus-overlay naming convention; older R zone designations retained hyphenated form in the legal text but 2023 reorganization maps show R-1A (unhyphenated) in signage. This profile uses the text-canonical hyphenated codes (R-1-A, R-1-B).

+ 6 more in Quirks & notes

Districts

res_mf 5res_sf 4res_th 2
CodeNameCategory Min lotHeight CoverageFAR Du/acParking Setbacks F/S/R
R-1-AResidential House Zone R-1-Ares_sf7,500 sf[4]40 ft[5]0.4[6]—[7]—[8]1[9]—[1] / 8[2] / 25[3]
R-1-BResidential House Zone R-1-Bres_sf5,000 sf[13]40 ft[14]0.4[15]—[16]—[17]1[18]—[10] / 8[11] / 25[12]
R-2Residential House Zone R-2res_sf[{'variant': 'detached', 'value': 4000, 'citation': '§D-302.1 Table'}, {'variant': 'IZ-detached', 'value': 3200, 'citation': '§D-302.1 Table'}, {'variant': 'semi-detached', 'value': 3000, 'citation': '§D-302.1 Table'}, {'variant': 'IZ-semi-detached', 'value': 2500, 'citation': '§D-302.1 Table'}, {'variant': 'all-other-structures', 'value': 4000, 'citation': '§D-302.1 Table'}] sf[22]40 ft[23]0.4[24]—[25]—[26]1[27]—[19] / 8[20] / 20[21]
R-3Residential House Zone R-3res_sf[{'variant': 'detached', 'value': 4000, 'citation': '§D-302.1 Table'}, {'variant': 'semi-detached', 'value': 3000, 'citation': '§D-302.1 Table'}, {'variant': 'attached', 'value': 2000, 'citation': '§D-302.1 Table'}, {'variant': 'IZ-attached', 'value': 1600, 'citation': '§D-302.1 Table'}, {'variant': 'all-other-structures', 'value': 4000, 'citation': '§D-302.1 Table'}] sf[31]40 ft[32][{'variant': 'attached-dwellings', 'value': 0.6, 'citation': '§D-304.1 Table'}, {'variant': 'places-of-worship', 'value': 0.6, 'citation': '§D-304.1 Table'}, {'variant': 'all-other-structures', 'value': 0.4, 'citation': '§D-304.1 Table'}][33]—[34]—[35]1[36]—[28] / —[29] / 20[30]
RF-1Residential Flat Zone RF-1res_th[{'variant': 'row-dwelling-or-flat', 'value': 1800, 'citation': 'Table E §201.1'}, {'variant': 'IZ-row-dwelling-or-flat', 'value': 1500, 'citation': 'Table E §201.1'}, {'variant': 'semi-detached', 'value': 3000, 'citation': 'Table E §201.1'}, {'variant': 'all-other-structures', 'value': 4000, 'citation': 'Table E §201.1'}] sf[40]35 ft[41]0.6[42]—[43]—[44]0.5[45]—[37] / —[38] / 20[39]
RF-2Dupont Circle Residential Flat Zone RF-2res_th[{'variant': 'row-dwelling-or-flat', 'value': 1800, 'citation': 'Table E §201.1 (general RF)'}, {'variant': 'semi-detached', 'value': 3000, 'citation': 'Table E §201.1'}, {'variant': 'all-other-structures', 'value': 4000, 'citation': 'Table E §201.1'}] sf[49]35 ft[50]0.6[51]—[52]—[53]0.5[54]—[46] / —[47] / 20[48]
RA-1Residential Apartment Zone RA-1res_mf—[58]40 ft[59]0.4[60]0.9[61]—[62][{'variant': 'multiple-dwelling-unit-buildings-RA', 'value': 0.33, 'note': '1 per 3 units in excess of 4 units per §C-701.5'}, {'variant': 'R-RF-zone-flats', 'value': 0.5, 'note': '1 per 2 dwelling units per §C-701.5 for R/RF zones — RA-1 follows MF rule'}][63]—[55] / —[56] / 20[57]
RA-2Residential Apartment Zone RA-2res_mf—[67]50 ft[68]0.6[69]1.8[70]—[71]0.33[72]—[64] / —[65] / —[66]
RA-3Residential Apartment Zone RA-3res_mf—[76]60 ft[77]0.75[78]3[79]—[80]0.33[81]—[73] / —[74] / —[75]
RA-4Residential Apartment Zone RA-4res_mf—[85]90 ft[86]0.75[87]3.5[88]—[89]0.33[90]—[82] / —[83] / —[84]
RA-5Residential Apartment Zone RA-5res_mf—[94]90 ft[95]0.75[96][{'variant': 'base', 'value': 5.0, 'citation': 'Table F §302.1'}, {'variant': 'apartment-house-or-hotel', 'value': 6.0, 'citation': 'Table F §302.1'}][97]—[98]0.33[99]—[91] / —[92] / —[93]

Confidence: confirmed partial under review not found

Overlays

HP
Historic Preservation — DC Inventory of Historic Sites
HP
Historic Landmark and Historic District Protection Act of 1978 (D.C. Law 2-144; D.C. Official Code §§6-1101 to 6-1115); ZR16 §I-807 (Downtown historic preservation credits)

Any lot containing a building or structure listed in the DC Inventory of Historic Sites, or contributing to a listed historic district, or nominated/pending nomination to the National Register of Historic Places by the SHPO (ZR16 §B definition of Historic District and Historic Landmark)

review_bodyDC Historic Preservation Review Board (HPRB)
review_typeHistoric Preservation Office review required for alterations, demolitions, and new construction affecting historic landmarks or contributing buildings in historic districts
downtown_FAR_creditBuildings in D zones on lots with historic landmarks may generate 1 credit per sq ft of undeveloped FAR up to +4.0 FAR (§I-807.4)
old_georgetown_actCommission of Fine Arts (CFA) review additionally required for permits in Georgetown historic district under 16 U.S.C. §491 et seq.
FED-HEIGHT
Federal Height Act Overlay
SPEC
Height of Buildings Act of 1910, §5 (36 Stat. 452; D.C. Official Code §§6-601.01 to 6-601.09); incorporated by ZR16 Subtitle A §402

City-wide; applies to all buildings and structures in the District of Columbia. Overrides any local zoning height limit that would exceed the federal statutory maximum.

business_streets_max_ft130
pennsylvania_ave_n_side_1st_to_15th_NW_max_ft160
residence_streets_max_ceiling_ft80
residence_streets_max_roof_parapet_ft85
general_ruleheight ≤ street_width_ft + 20 ft
residence_street_further_limitheight ≤ street_width_ft - 10 ft (with exceptions for narrow streets)
corner_lotsDetermined by width of the wider street
FP
100-Year Floodplain Overlay
FP
ZR16 Subtitle C §1102 (Floodplain provisions)

Any lot within the 100-year floodplain boundary as shown on FEMA Flood Insurance Rate Maps (FIRMs) adopted by DC. Primarily affects Anacostia River and Potomac River-adjacent properties.

residential_1_2_unitSpecial exception required for 1-2 unit residential within 100-year floodplain (§C-1102.4(a))
required_documentationSite plan with floodplain boundaries and base flood elevations certified by PE/architect; flood-resistant design description; evacuation plan
agency_referralApplications referred to DOEE, FEMS, MPD, and DC Homeland Security
local_freeboardNot captured — DOEE flood resistance standards apply; exact freeboard requirement not confirmed in ZR16 primary source review
local_freeboard_statuspartial
local_freeboard_retrieval_failure_reasonZR16 §C-1102 references DOEE standards but does not state a specific freeboard amount; a separate DOEE rulemaking governs. Not retrieved in this pass.
NCPC
NCPC Federal Interest Review
SPEC
National Capital Planning Act of 1952; 40 U.S.C. §§8701–8724; ZR16 Subtitle Z (NCPC referral provisions); NCPC Submission Guidelines effective 2026-01-08

Projects on or adjacent to federal-interest land in DC as defined by NCPC submission criteria; Zoning Commission actions affecting the Federal City Comprehensive Plan

review_stagesConcept / Preliminary / Final submission stages (updated per 2026-01-08 NCPC guidelines)
review_bodyNational Capital Planning Commission
statutory_review_window30 days from referral; ZC may proceed after 30 days without NCPC report (ZR16 Subtitle Z)
impactDelays and may condition local zoning approvals on federal compliance for qualifying projects
IZ
Inclusionary Zoning (IZ) Program
AH
ZR16 Subtitle C Chapter 10 (Inclusionary Zoning); amended by IZ Plus penthouse/rooftop expansion (ZC action Dec 2024); NYE zone 8% set-aside (2024-09-12)

New residential construction or additions of 10 or more units in zones where IZ is required (RF, RA, MU, NMU, D zones — excludes R-1-A and R-1-B per §D-105.1)

citywide_affordable_pct_wood_frame10
citywide_affordable_pct_steel_concrete8
nye_zone_pct8
iz_plus_penthouse_option_1Reserve units at 50% MFI within penthouse
iz_plus_penthouse_option_2In-lieu HPTF payment equal to half penthouse market value
r1a_r1b_exemptionR-1-A and R-1-B zones exempt from IZ (§D-105.1)
AP
Airport/Airspace Overlay
AP

Not applicable — Washington DC does not have a commercial airport within DC boundaries. Reagan National Airport is in Arlington, VA; Dulles is in Loudon/Fairfax, VA. DC airspace is subject to FAA SFRA (Special Flight Rules Area) but this is flight operations, not building height zoning overlay.

TOD
TOD / Transit-Oriented Development Overlay
TOD

Not applicable as a named stand-alone overlay in ZR16. DC addresses transit-oriented development through base zone designations (MU, NMU zones mapped around Metro stations) and Subtitle G/H provisions rather than a separate TOD overlay chapter.

State preemptions

Height of Buildings Act of 1910 (36 Stat. 452; D.C. Official Code §§6-601.01 to 6-601.09)applies
Qualifying condition
DC is a federal district; the Height Act applies city-wide as federal law. All buildings subject to height caps: ≤130 ft on business streets, ≤160 ft on N side Pennsylvania Ave between 1st and 15th St NW, ≤80/85 ft on residence streets (ceiling/parapet), further limited to street_width + 20 ft general rule (§5 of Act). ZR16 zone-specific heights operate within these federal caps.
Effect
Federal statutory cap on building heights supersedes any local zoning height allowance that would exceed it. ZR16 Subtitle A § 402 incorporates by reference.
Home Rule Act of 1973 (D.C. Code §1-201.01 et seq.)applies
Qualifying condition
DC is a federal district, not a state. The Home Rule Act governs DC's legislative authority. DC Council can enact zoning regulations subject to Congressional review (30-day review window for most legislation). Congress retains override authority.
Effect
Establishes the jurisdictional framework for DC local governance. Unlike states, DC cannot enact laws that exceed Congressional authorization; federal preemption via Congress supplants state-preemption doctrine.
NCPC Submission Guidelines update (40 U.S.C. §§8701–8724; ZR16 Subtitle Z)applies
Qualifying condition
NCPC review applies to projects on or adjacent to federal-interest land in DC. Updated submission guidelines effective 2026-01-08 tighten federal review stages for concept/preliminary/final submissions.
Effect
Federal prerequisite for qualifying development projects; delays or conditions local zoning approvals where federal land interest is triggered.

Adopted building codes

District-wide

IBC
2015
IRC
2015
NEC
2014
IFC
2015
IECC (Residential)
2015
IECC (Commercial)
2015

Click a code label to open its state-by-state adoption atlas.

Amendment history

DateKindCitation
2026-05-26retrieved atResearch date for this V2 profile
2023-08-25amendment effectiveZR16 reorganization — ZC Order No. 18-16/19-27-19-27B; reintroduced base-zone-plus-overlay naming, renumbered districts (R-1-A became R-1A nomenclature in signage, codes retain hyphenated form in text)
2016-09-06effective63 DCR 2447 (March 4, 2016 – Part 2), ZR16 took effect September 6, 2016

Quirks & notes

  • DC is a federal district — state preemption framework does not apply. Federal constraints (Height Act, Home Rule Act, NCPC review) documented in federal_overlay_framework and state_preemptions_applicable as functional equivalents.
  • Height Act (1910, federal) caps all building heights city-wide; ZR16 zone heights are subservient. On most residential streets, the Height Act residence street cap (80/85 ft ceiling/parapet, further limited by street width minus 10 ft) is more restrictive than the RA zone height allowances for RA-4/RA-5.
  • ZR16 reorganized in August 2023 — reintroduced base-zone-plus-overlay naming convention; older R zone designations retained hyphenated form in the legal text but 2023 reorganization maps show R-1A (unhyphenated) in signage. This profile uses the text-canonical hyphenated codes (R-1-A, R-1-B).
  • R and RF zones do not use FAR as a density control — lot occupancy (lot_coverage) is the primary bulk control. RA zones use both FAR and lot occupancy.
  • Front setbacks in all R and RF zones are contextual — must be within the range of existing setbacks on the same block face. There is no fixed numeric minimum setback in ZR16 Subtitles D and E.
  • Rear yard in RA-2 through RA-4 is height-dependent (4 in/ft, min 15 ft); RA-5 uses 3 in/ft minimum 12 ft — no single fixed numeric value.
  • Inclusionary Zoning (IZ) reduced lot dimension variants are embedded in the district tables (§D-302.1): R-2 IZ detached = 3,200 sq ft / 32 ft width; R-3 IZ attached = 1,600 sq ft / 16 ft width.
  • Georgetown Historic District has dual review: ZR16 HP provisions + federal Old Georgetown Act (16 U.S.C. §491) requiring Commission of Fine Arts approval for permits.
  • Template-bleed fully confirmed in v1 record: all 11 districts had identical 5,000 sq ft min lots, identical 5 or 10 ft rear setbacks, identical parking=2. These values did not match ZR16 primary source for any district.

Formulas

Definitions

height
Vertical distance from the grade level of the sidewalk or average grade at building front to the highest point of the roof or parapet. Height Act (36 Stat. 452) establishes federal caps; ZR16 sets zone-specific limits within those caps.
lot_coverage
Percentage of lot area covered by all structures (principal + accessory). Termed 'lot occupancy' in ZR16.
far
Gross floor area divided by lot area. Applicable in RA and D zones; R and RF zones are controlled primarily by lot occupancy (not FAR).
du_ac
Not the primary density control in DC R zones. Density controlled by minimum lot area per dwelling type (§D-302, §E-201, §F-302).
setback_front
ZR16 R zones: front setback must be within the range of existing front setbacks of buildings on the same side of the street in the block (contextual, not a fixed number). §D-305.1.
setback_side
Minimum side yard dimension set per zone in Subtitles D, E, F.
setback_rear
Minimum rear yard depth set per zone in Subtitles D, E, F.
parking
Spaces per dwelling unit (residential) or per 1,000 sq ft (commercial) per §C-701.5. R/RF zone flats: 1 per 2 units; SFD: 1 per principal dwelling.

Capacity calculations

max_footprint_sf
lot_area_sf * lot_occupancy_fraction
max_gfa_sf
lot_area_sf * far (RA/D zones); R/RF zones use lot_occupancy not FAR
height_limit_federal
min(ZR16_zone_max, Height_Act_limit) where Height_Act_limit = street_width_ft + 20 ft (general) or 130 ft (business streets) or 160 ft (N side Pennsylvania Ave, 1st–15th St NW)

Massing explorer

Interactive 3D comparison across every district. Drag to orbit, scroll to zoom, use the slider to walk districts, and toggle applicable overlays in the right-side panel.

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District Category Height FAR Coverage Setbacks Parking Density Min lot Overlays

Sources & references

Primary source
https://online.encodeplus.com/regs/washington-dc/index.aspx
Citations
  1. [1] §D-305.1
  2. [2] §D-307.1
  3. [3] §D-306.1
  4. [4] §D-302.1
  5. [5] §D-303.1
  6. [6] §D-304.1
  7. [7] n
  8. [8] n
  9. [9] §C-701.5
  10. [10] §D-305.1
  11. [11] §D-307.1
  12. [12] §D-306.1
  13. [13] §D-302.1
  14. [14] §D-303.1
  15. [15] §D-304.1
  16. [16] n
  17. [17] n
  18. [18] §C-701.5
  19. [19] §D-305.1
  20. [20] §D-307.1
  21. [21] §D-306.2
  22. [22] §D-302.1
  23. [23] §D-303.1
  24. [24] §D-304.1
  25. [25] n
  26. [26] n
  27. [27] §C-701.5
  28. [28] §D-305.1
  29. [29] §D-307.3
  30. [30] §D-306.2
  31. [31] §D-302.1
  32. [32] §D-303.1
  33. [33] §D-304.1
  34. [34] n
  35. [35] n
  36. [36] §C-701.5
  37. [37] §E-305.1
  38. [38] §E-307.3
  39. [39] §E-306.1
  40. [40] §E-201.1
  41. [41] §E-303.1
  42. [42] §E-304.1
  43. [43] n
  44. [44] n
  45. [45] §C-701.5
  46. [46] §E-405.1
  47. [47] §E-407
  48. [48] §E-406
  49. [49] §E-201.1
  50. [50] §E-403.1
  51. [51] §E-404.1
  52. [52] n
  53. [53] n
  54. [54] §C-701.5
  55. [55] n
  56. [56] §F-306.2a
  57. [57] §F-305
  58. [58] §F-201
  59. [59] §F-303.1
  60. [60] §F-304.1
  61. [61] §F-302.1
  62. [62] n
  63. [63] §C-701.5
  64. [64] n
  65. [65] §F-306.2b
  66. [66] §F-305
  67. [67] n
  68. [68] §F-303.1
  69. [69] §F-304.1
  70. [70] §F-302.1
  71. [71] n
  72. [72] §C-701.5
  73. [73] n
  74. [74] §F-306.2b
  75. [75] §F-305
  76. [76] n
  77. [77] §F-303.1
  78. [78] §F-304.1
  79. [79] §F-302.1
  80. [80] n
  81. [81] §C-701.5
  82. [82] n
  83. [83] §F-306.2b
  84. [84] §F-305
  85. [85] n
  86. [86] §F-303.1
  87. [87] §F-304.1
  88. [88] §F-302.1
  89. [89] n
  90. [90] §C-701.5
  91. [91] n
  92. [92] §F-306.2b
  93. [93] §F-305
  94. [94] n
  95. [95] §F-303.1
  96. [96] §F-304.1
  97. [97] §F-302.1
  98. [98] n
  99. [99] §C-701.5

Research status

Publication gates

primary url presentpassedsource.primary_url = https://online.encodeplus.com/regs/washington-dc/index.aspx — HTTPS, not an aggregator domain; DC Office of Zoning-maintained viewer
no aggregator citedpassedscan clean — no Zoneomics, Steadily, SitePlanGuide, SitePlanCreator, Propwire, Zonara, or Unzoned references anywhere in record
confidence tags full formpassed48 confirmed fields carry §-citations (e.g. c§D-302.1, c§D-303.1, c§D-304.1, c§D-306.1, c§D-307.1, c§F-302.1, c§F-303.1, c§F-304.1, c§C-701.5, c§E-303.1, c§E-304.1, c§E-306.1). Partial fields carry paired what_is_confirmed/what_is_missing companions per FM-8. No bare 'c' confidence tags.
overlays have parameters trigger confidencepassed6 active overlays (HP, FED-HEIGHT, FP, NCPC, IZ, TOD-not_found, AP-not_applicable) each have non-empty params, geographic_trigger, status, and confidence citation. TOD and AP documented as not_found/not_applicable with search_performed/reason.
preempt section city specificpassedDC is not a CA/TX/FL/WA/OR/MT/CO/UT/AZ/NJ/CT active-preemption state; Gate 5 applies only to those states. DC has no state preemption laws. Federal constraints documented in state_preemptions_applicable with qualifying_condition_checked for each entry (Height Act city-wide applicability, Home Rule Act governance framework, NCPC 2026-01-08 update). Gate satisfied: non-empty array with city-specific qualifying_condition_checked on all 3 entries.

Data quality

72%completeness48 confirmed18 partial9 not found
Documented gaps
  • RA-2 through RA-5 minimum lot area not found in Subtitle F Chapter 3 (general RA lot area appears BZA-determined per §F-201.4 for special exceptions)
  • MU, NMU, D, PDR, and Special Purpose zones (Subtitle K) not researched in this pipeline run — only R, RF, RA residential zones captured
  • Front setbacks for RA zones not found in Subtitle F primary source
  • DOEE freeboard requirement for floodplain overlay not retrieved
  • Parking exemption provisions (§C-702 and Metro proximity exemptions) not fully captured