Washington, DC · Title 11 DCMR (2016 Zoning Regulations)
The R-1-A zone is DC's lowest-density single-family residential zone, found in the District's most spacious single-family neighborhoods. Only one principal dwelling unit is permitted per lot, and an accessory dwelling unit is allowed in an accessory building. The R zones are governed by lot occupancy rather than floor area ratio -- see the development standards for the minimum lot area, height and lot-occupancy limits.
Development standards in R-1-A
Maximum height
40 ft
Maximum stories
3
Maximum lot coverage
40%
Minimum lot size
7500 sq ft
Minimum lot width
75 ft
Max density
1 units/acre
Front setback
20 ft
Side setback
8 ft
Rear setback
25 ft
Development governed by lot occupancy / building form, not FAR (see development-standards matrix).
Federal Heights Act (1910) limits apply: 90 ft on residential streets, 110 ft on commercial streets, 130 ft on Pennsylvania Avenue. These federal limits cannot be exceeded by any local zoning approval or PUD.
Development standards for this market are not yet checked against a committed copy of the ordinance. Use the ordinance link below as the authoritative source.
Permitted uses in R-1-A
AllowedAgricultural – large uses (excluding private stable) Private stable is excluded; Subtitle U §202.1(c)
AllowedAgricultural – residential uses (excluding private stable) Private stable is excluded; Subtitle U §202.1(d)
AllowedCar-sharing spaces on an unimproved lot No more than two (2) spaces permitted; Subtitle U §202.1(e)
AllowedChancery existing on September 22, 1978 Subject to conditions: limited to government that occupied on February 23, 1990; no additional structures; no expansion; reconstruction allowed if destroyed but limited to site as of February 23, 1990; reconstruction not subject to Subtitle C Chapter 2; Subtitle U §202.1(f)
AllowedChild development/elderly development center located in a District of Columbia public school or public recreation center operated by the District of Columbia Government Written permission required from Chancellor of DC Public Schools or Director of managing government agency; Subtitle U §202.1(g)
AllowedEmergency shelter Not more than four (4) persons, not including resident supervisors or staff and their families; Subtitle U §202.1(h)
AllowedGovernment, local uses Subtitle U §202.1(i)
AllowedHealth care facility For not more than six (6) persons not including resident supervisors or staff and their families. May accommodate seven (7) to eight (8) persons provided no existing health care facility for seven (7) or more persons exists in the same square or within 1,000 ft. of the subject property; Subtitle U §202.1(j)
AllowedInstitutional, religious-based uses Does not include rescue mission or temporary revival tents; Subtitle U §202.1(k)
AllowedPrivate garage, as a principal use Designed to house no more than two (2) motor vehicles, not exceeding 450 sq. ft., subject to Subtitle D Chapter 50; Subtitle U §202.1(l)
AllowedPublic education buildings and structures, public recreation and community centers, and public libraries Subject to development standards of Subtitle C Chapter 16; Subtitle U §202.1(m)
AllowedPublic schools, reuse of a former District of Columbia public school Subject to conditions of Subtitle U § 252; Subtitle U §202.1(n)
AllowedTemporary buildings for the construction industry Must be incidental to erection of buildings or other structures permitted by this section; Subtitle U §202.1(o)
AllowedTemporary use of premises by fairs, circuses, or carnivals Subject to Title 19 DCMR Chapter 13 (Amusements, Parks, and Recreation); Subtitle U §202.1(p)
AllowedTransportation infrastructure Must be operated directly or under contract by the District government or the Washington Metropolitan Area Transit Authority; Subtitle U §202.1(q)
Not AllowedCorner store Permitted only in R-Use Group C as a matter of right; R-1A is in R-Use Group A and therefore this use does not apply; Subtitle U §202.2
AllowedTwo (2) boarders within the principal dwelling Permitted as matter of right in all R zones; Subtitle U §250.1(a)
AllowedCar-sharing spaces (no more than two) Neither space may be devoted to required parking; permitted in all R zones; Subtitle U §250.1(b)
AllowedChild development home or elderly day care home Must be in caregiver's principal residence; max one sign (144 sq. in.); no stock in trade sold; max one non-resident employee; no non-domestic mechanical equipment; Subtitle U §250.1(c)
AllowedHome Occupation Subject to conditions of Subtitle U § 251; Subtitle U §250.1(d)
AllowedBusiness support and technology services Permitted as home occupation; subject to general HOP requirements in 251.2 and 251.3; Subtitle U §251.1(a)
AllowedChild development home (up to 6 individuals, 15 years of age or less) No more than two (2) non-resident persons engaged or employed; Subtitle U §251.1(b)(1)
AllowedExpanded child development home (7 to 9 individuals, 15 years of age or less) No more than 3 non-resident employees; minimum 35 sq. ft. floor area per individual; no more than 320 sq. ft. of dwelling floor area utilized; Subtitle U §251.1(b)(2)
ConditionalExpanded child development home (10 to 12 individuals, 15 years of age or less) Permitted by special exception by the Board of Zoning Adjustment under Subtitle X and 251.6; minimum 35 sq. ft. floor area per individual required; Subtitle U §251.1(b)(3)
AllowedCosmetologist, hair stylist, or barber Permitted as home occupation; subject to general HOP requirements; Subtitle U §251.1(c)
AllowedCottage food business Permitted as home occupation; subject to general HOP requirements; Subtitle U §251.1(d)
AllowedDressmaking, sewing, and tailoring Permitted as home occupation; subject to general HOP requirements; Subtitle U §251.1(e)
AllowedHome crafts, graphic arts, photography, and other fine arts occupations (home studio) No more than 60% of floor area of dwelling unit may be devoted to the studio; Subtitle U §251.1(f)
AllowedHome office of a businessperson, non-profit organization, sales person, or manufacturer's representative Dwelling shall not be used as a gathering point for workers on the way to another work site; Subtitle U §251.1(g)
AllowedHome office of a physician, dentist, or other health care or licensed medical professional No other medical or dental practice shall be on the site; Subtitle U §251.1(h)
AllowedHome office of a scientist, clergyman, inventor, academician, licensed health care professional (other than 251.1(h)), or other professional person Permitted as home occupation; subject to general HOP requirements; Subtitle U §251.1(i)
AllowedLodging (bed and breakfast) Dwelling must be owner-occupied as principal residence; not permitted in multiple dwelling building; breakfast only served to overnight guests; maximum 2 sleeping rooms by right (may be increased to 4 or 6 via special exception or historic landmark status per 251.6(b)); 1 parking space per 2 guest sleeping rooms required; no cooking facilities in rented rooms; Subtitle U §251.1(j)
ConditionalLodging (increased sleeping rooms – up to 4, or up to 6 in historic landmark/contributing historic district) Maximum sleeping rooms may be increased to 4, or to 6 for historic landmark or contributing historic district property, via special exception under 251.6(b); number reduced by 1 for each long-term boarder (30+ days); Subtitle U §251.1(j)(4)(A)
AllowedPractitioner performing and being paid for a service resulting in creation of a product A practitioner may perform and be paid for a service even if it results in the creation of a product; Subtitle U §251.1(k)
AllowedSales directly associated with home occupation (including yard sales, garage sales, home sales parties – up to 5 per 12-month period) Items sold must be directly associated with the home occupation; up to 5 yard/garage/home sales parties per 12-month period by right; no general retail sales or sales to customers without appointments; Subtitle U §251.1(l)
ConditionalSales directly associated with home occupation (6th sale in 12-month period) One additional sale (6th total) in a 12-month period may be permitted by the Board of Zoning Adjustment under 251.6; Subtitle U §251.1(l)(2)
AllowedTutoring and instruction (not more than 5 students at one time) Includes academic tutoring, dance, languages, culinary arts, musical instrument, and similar activities; maximum 5 students at any one time; Subtitle U §251.1(m)
AllowedHome occupation in an accessory apartment No more than 6 visitors or clients per day; no related sales; no lodging or overnight stays as part of the home occupation; Subtitle U §251.1(n)
Not AllowedAnimal sales, care, and boarding Explicitly prohibited as a home occupation under 251.5 except as explicitly permitted by 251.1; Subtitle U §251.5(a)
Not AllowedEntertainment, assembly, and performing arts Explicitly prohibited as a home occupation under 251.5 except as explicitly permitted by 251.1; Subtitle U §251.5(b)
Not AllowedFirearms sales Explicitly prohibited as a home occupation under 251.5; Subtitle U §251.5(c)
Not AllowedMotor vehicle sales, service, or repair Explicitly prohibited as a home occupation under 251.5; Subtitle U §251.5(d)
Not AllowedProduction, distribution, and repair Explicitly prohibited as a home occupation under 251.5; Subtitle U §251.5(e)
Not AllowedRetail sales Explicitly prohibited as a home occupation under 251.5; general retail sales or sales to customers without appointments not permitted; Subtitle U §251.5(f)
Not AllowedSexually-based business establishment Explicitly prohibited as a home occupation under 251.5; Subtitle U §251.5(g)
Not AllowedWaste-related services Explicitly prohibited as a home occupation under 251.5; Subtitle U §251.5(h)
AllowedAccessory apartment in principal dwelling Permitted as matter of right in R-1A. Minimum gross floor area of house must be 2,000 sq. ft. Accessory apartment unit may not exceed 35% of house GFA. Additional entrance, if created, shall not face a street.; Subtitle U §253.2, 253.7(a), 253.7(b), 253.7(c)
ConditionalBalcony or projecting windows for accessory apartment Inclusion of a balcony or projecting windows for the accessory apartment requires Board of Zoning Adjustment special exception approval.; Subtitle U §253.11
"Conditional" means the use generally requires a public hearing or special-exception approval — a very different timeline and risk profile from a by-right permit.
This is the zone. What about the parcel?
Zone rules are the starting point — the answer for a specific property also depends on lot
size, overlays, existing improvements and site conditions. Run a free address lookup to see
what applies to one property.
Standards as recorded by ZoneScore: 11 DCMR Subtitle D, Chapter 3 (R-1-A, R-1-B, R-2, R-3 zones)
Development standards are derived from the DC Office of Zoning's published development-standards table and checked against Title 11 DCMR; use permissions follow Subtitle U.