Baltimore ADU Permit Process & Fees Guide

Housing and Building Standards Maryland 3 Minutes Read ยท published February 08, 2026 Flag of Maryland

This guide explains the accessory dwelling unit (ADU) permitting process, typical fees, timelines and enforcement in Baltimore, Maryland. It is written for homeowners, architects and contractors who want to convert or add a secondary dwelling on a residential lot. The article summarizes application steps, likely inspections, common violations and appeal routes administered by Baltimore city departments.

Check local zoning before design work to avoid delays.

Overview of ADU Permitting in Baltimore

In Baltimore, ADU projects generally require review under the city zoning rules and a building permit. The city evaluates zoning compliance (setbacks, lot coverage, parking) and building safety (structural, mechanical, electrical, plumbing). Expect plan review, permit fees and at least one site inspection during construction and a final inspection before occupancy.

Penalties & Enforcement

Baltimore enforces zoning and building rules through code enforcement and permitting divisions. Specific monetary fines and escalation schedules for unauthorized ADUs are not specified in a single consolidated city page and may depend on the applicable code section or hearing decision.

  • Monetary fines: not specified on a single consolidated city page; amounts vary by code section and case.
  • Escalation: first, repeat and continuing violations may result in higher fines or daily penalties where the ordinance allows; specific ranges are not specified on a single consolidated city page.
  • Non-monetary sanctions: stop-work orders, orders to vacate, mandatory permit or plan submission, lien or abatement actions, or court enforcement may be used.
  • Enforcement offices: code enforcement and permitting divisions handle inspections, complaints and notices to comply.
  • Appeals and review: administrative appeals or hearings may be available; time limits and filing procedures depend on the specific notice or ordinance that issued the action and are not specified on a single consolidated city page.
If you receive a notice, act quickly to file an appeal or remedy to avoid escalating penalties.

Applications & Forms

Required forms vary by project scope. Typical requirements include a building permit application, construction plans, site plan or survey showing dimensions, and trade permits for electrical, plumbing, and mechanical work. Where a zoning variance or exception is needed, separate hearing application forms may apply. Specific form names, numbers and fee tables are published by the city permitting office or planning department.

Common Violations and Typical Responses

  • Unauthorized occupancy of an ADU without an approved permit or final inspection.
  • Construction without a building permit or without required trade permits.
  • Zoning noncompliance: setbacks, lot coverage or parking violations.
  • Failure to correct unsafe conditions after an inspection.
Many compliance issues are resolved by permitting the existing work or by submitting corrective plans.

Action Steps

  • Confirm zoning for your property and whether an ADU is allowed.
  • Prepare construction drawings and trade plans to submit with the permit application.
  • Submit permit applications and pay plan review and permit fees.
  • Schedule required inspections and obtain final approval before occupancy.

FAQ

Do I need a permit to build or convert an ADU?
Yes. Building permits and applicable trade permits are required for new construction or conversion to an ADU; zoning review is also required.
How long does plan review take?
Review times vary by workload and complexity; the city posts current plan-review timelines on permitting pages or by request.
What if my property is not zoned for ADUs?
If the zoning does not allow an ADU, you may pursue a zoning variance or consider redesigning to meet zoning standards, subject to hearing processes.

How-To

  1. Verify zoning and code requirements for ADUs on your property.
  2. Hire a design professional or prepare plans that meet building and zoning rules.
  3. Complete and submit the building permit application with required documents and pay fees.
  4. Address plan-review comments, revise plans if requested, and obtain permit approval.
  5. Schedule and pass required inspections during construction and at completion.
  6. Receive final approval and certificate of occupancy before renting or occupying the ADU.
Always obtain final inspection and approval before occupying an ADU to avoid enforcement action.

Key Takeaways

  • ADUs in Baltimore require both zoning review and building permits.
  • Fee amounts and fine schedules are set by permitting and code sections and should be confirmed with the city.
  • Contact city permitting and code enforcement early to clarify requirements and avoid delays.

Help and Support / Resources

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