Zoning, building permits and septic rules in Baltimore, Maryland

Baltimore’s own rules

• Building permitRequired

  Construction, alteration, repair, demolition or moving of any structure inside Baltimore city, issued by the Baltimore city building official

  • Permit required before work begins (IBC 105.1 as adopted by Baltimore city).
  • The list of covered work in 105.1 also includes change of use, grading or excavating, and lot-line moves affecting structures; exemptions were not reviewed.

  “a permit issued by the building official is required before any person may do any of the following work”

• Building code adoptedAdopted (with conditions)

  Construction inside Baltimore city limits

  • Baltimore city's building code is the 2024 edition; the IBC section 111 text is adopted with local modifications (occupancy permit terminology).

  “baltimore city code building, fire, and related codes 2024 edition part ii international building code chapter 1 scope and administration”

• Local zoningPresent (with conditions)

  All land inside Baltimore city limits; Baltimore city administers its own zoning code (Baltimore City Code Article 32, Zoning).

  • Zoning is administered by Baltimore city itself, not by a county.
  • Use and bulk rules differ by district; see the district-specific claims.

  “the r-1 detached residential zoning district is intended for neighborhoods of detached dwellings located on lots of at least 7,300 square feet.”

• Zoning districtsPartial

  Zoning districts in Baltimore city, Article 32

  • Only the detached and semi-detached residential districts R-1a through R-4 (Table 8-401) were verified; rowhouse, multi-family, commercial and industrial districts were not reviewed.

  “categories specifications (per district) r-1a r-1b r-1c r-1d r-1e r-1 r-2 r-3 r-4”

• Minimum lot sizeDistrict specific (with conditions)

  Detached dwelling lots in the R-1a district (largest-lot detached district, the rural-residential-type district in Baltimore city) inside Baltimore city

  • Table 8-401 lists 2 acres for detached dwellings in R-1a; all other uses 2 acres.

  minimum lot area, dwelling detached, R-1a: >= 2 acres

  “dwelling: detached or semi-detached 2 acres 1 acre 21,780 sq.ft. 14,520 sq.ft. 9,000 sq.ft. 7,300 sq.ft. 5,000 sq.ft. 5,000 sq.ft. 3,000 sq.ft.”

• SetbacksDistrict specific (with conditions)

  Detached dwellings in the R-1 Detached Residential District inside Baltimore city

  • Front yard 30 ft applies only if less than 50% of lots on the blockface are developed; if 50% or more are developed, the front yard is the lesser of the average front-yard depth of improved lots or 40 feet (Table 8-401 footnote 1).
  • Interior-side yard for detached dwelling 5 ft; corner-side yard 10 ft; rear yard 30 ft, per the same Table 8-401 column.

  minimum front yard, R-1: >= 30 feet (Table 8-401 footnote 1 blockface rule) · minimum interior-side yard, detached dwelling, R-1: >= 5 feet · minimum corner-side yard, R-1: >= 10 feet · minimum rear yard, R-1: >= 30 feet

  “minimum front yard all uses 1 40 feet 40 feet 40 feet 40 feet 30 feet 30 feet 30 feet 25 feet 25 feet”

  One more reviewed finding on this topic

  • District specific (with conditions) — Detached dwellings in the R-1a district inside Baltimore city (largest-lot district)

    “minimum front yard all uses 1 40 feet 40 feet 40 feet 40 feet 30 feet 30 feet 30 feet 25 feet 25 feet”

• Lot coverageDistrict specific (with conditions)

  All uses in the R-1 Detached Residential District inside Baltimore city

  • Maximum impervious surface for all uses in R-1 is 50% (Table 8-401 impervious row).

  maximum lot coverage, all uses, R-1: <= 40 %

  “maximum lot coverage all uses 35% 35% 35% 35% 35% 40% 40% 45% 45%”

  One more reviewed finding on this topic

  • District specific (with conditions) — All uses in the R-1a district inside Baltimore city

    “maximum lot coverage all uses 35% 35% 35% 35% 35% 40% 40% 45% 45%”

• Building heightDistrict specific (with conditions)

  All uses in the R-1 Detached Residential District inside Baltimore city

  • Same 35-foot maximum applies to every detached and semi-detached district in Table 8-401.

  maximum building height, all uses, R-1: <= 35 feet

  “maximum building height all uses 35 feet 35 feet 35 feet 35 feet 35 feet 35 feet 35 feet 35 feet 35 feet”

  One more reviewed finding on this topic

  • District specific (with conditions) — All uses in the R-1a district inside Baltimore city

    “maximum building height all uses 35 feet 35 feet 35 feet 35 feet 35 feet 35 feet 35 feet 35 feet 35 feet”

• Who permits septicLocal (with conditions)

  On-site sewage disposal (septic) inside Baltimore city limits

  • Private septic is allowed only with the written permission of the Baltimore city code official; Baltimore city code section 317.2 says private systems must comply with COMAR 26.04.02.

  “private septic tank systems may only be installed with the written permission of the code official.”

• Septic permitLimited

  Installation of a private septic tank system inside Baltimore city

  • Installation requires the written permission of the code official; the permit form and fees were not located.

  “private septic tank systems may only be installed with the written permission of the code official.”

• Off-grid sanitationLimited

  Private on-site sanitation (septic tank) inside Baltimore city

  • Only with written permission of the code official; otherwise a connection to public sewer is required under section 317.1.

  “private septic tank systems may only be installed with the written permission of the code official.”

• Mandatory utility hookupWater and sewer (with conditions)

  A building with plumbing fixtures inside Baltimore city, including a new home

  • Connection to public water and public sewer is required unless otherwise authorized by a National Pollutant Discharge Elimination System permit issued under title 9 of the state environment article.
  • Private septic is an exception only with written permission (see septic claims).

  “the water distribution and sewer system of any building in which plumbing fixtures are installed must be connected to a public water supply system and to a public sewer system unless otherwise authorized by a national pollutant discharge elimination system permit issued under title 9 of the state environment article.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Baltimore or Baltimore City directly.

• Owner-builder exemption — Owner-builder permit exemption inside Baltimore city
• Inspections — Inspections for construction inside Baltimore city
• Certificate of occupancy — Certificate of occupancy (called an occupancy permit in Baltimore city) for work inside Baltimore city
• Minimum dwelling size — Minimum dwelling floor area inside Baltimore city
• Living in an RV — RV occupancy on private land inside Baltimore city

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.