ADUs are allowed in Unincorporated DorchesterTypes:Internal
Types:Internal
Accessory Dwelling Unit (ADU) Rules for Unincorporated Dorchester, MD
Is your property eligible for an ADU?
# of Properties
9,930
Owner-occupied
61%
Zoning districts
21
Avg Home Value
$208,261
Median Lot Size
1.31 acres
Avg Income
$80,664
Residential Types:
9,930 housing units
Residential
100%
Zoning Districts:
13,158 parcels · 21 districts
AC
36%(4,750)
RR
22%(2,946)
RC
17%(2,222)
SR
11%(1,486)
Other
13%(1,754)
ADU Rules
What can you build in Unincorporated Dorchester, MD?
Unincorporated Dorchester, MD follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.
Eligibility
- –Internal / Attached ADU: By Right
- –Detached ADU: Not permitted
Interior / Attached ADU Size Limits
- –Maximum size of 800 sq ft for an internal accessory apartment in an owner-occupied single-family dwelling
- –Maximum size of one-third of the total area of the single-family dwelling for an internal accessory apartment in an owner-occupied home
Max Units
- –SFD: 1 internal/attached per lot; 1 detached (guest house) per parcel of record as of 12/1/1985.
- –Non-residential: 1 business dwelling per site.
Owner Occupancy
- –Owner must occupy the principal dwelling or the ADU
Parking
- –1 space/ADU; deviations allowed via site plan review by the Planning Commission; off-site parking allowed if pedestrian access to parking is within 200 ft of the dwelling entrance
Rental Restrictions
- –Guest house not allowed as a rental unit; guest cottages not allowed as permanent residences or for rentals other than for guests attending events at the principal structure.
ADU State Law
What can you build in Maryland?
- –Local-law mandate: By Oct 1, 2026, each legislative body must adopt a local law authorizing ADUs under this section.
- –Local zoning mostly remains: The subtitle generally does not alter local zoning power except as provided, but locals must establish policies that further the subtitle's intent.
- –Definition-based size cap: An ADU must be ≤ 75% of the size of the primary SF detached dwelling and subordinate in use; ADUs may be detached or attached.
- –Density/growth limits: ADUs must be excluded from density calculations and from measures limiting residential growth that pertain to the lot/parcel/tract.
- –Setbacks: Local law cannot set side/rear setbacks that exceed existing accessory-structure setbacks.
- –Parking: If a jurisdiction adds off-street parking requirements, it must consider specified factors and provide a waiver process, and must complete a parking study before adopting such requirements.
- –Alley access option: Local law may prohibit converting an accessory structure to an ADU if only vehicular access is from an alley.
- –Codes/adequate facilities: Local law must provide for ADU construction meeting public health/safety/welfare standards, including building codes and adequate public facilities provisions.
What's allowed on your lot?
These are the municipality-wide rules. What's allowed on a specific property also depends on state laws, setbacks, floor area ratio, lot coverage, environmental constraints, topography, and other property-specific factors. Search your address on FutureLot to see what's allowed on your property.
Check my propertyHow can we help you?
Get matched with trusted local builders
Understand what's allowed on your property
Learn the key rules and size limits for ADUs
Is your property eligible for an ADU?
ADU rules in other Maryland municipalities
Rules change at the town line. Check the municipality your property is actually in.
Dorchester County