Permit Requirements

Baltimore City and Baltimore County are two separate governments with two separate permit offices, two separate codes, two separate portals and two separate inspection lines. A county permit means nothing in the city, and a city permit means nothing in the county. A Baltimore mailing address does not settle which one you are in.

In the city, permits come from the Department of Housing and Community Development, filed online through its E-Permits portal, with walk-in help at the One Stop Shop on East Fayette Street. In the county, permits come from the Department of Permits, Approvals and Inspections, known as PAI, filed through the county's online permit portal, with walk-in help at the County Office Building in Towson. Both require you to apply online.

Maryland requires every jurisdiction in the state to enforce the same edition of the same model codes. As of August 2026 that is the 2021 International Building Code, Residential Code and Energy Conservation Code. Local governments then amend them, which is exactly why the details below differ between the city and the county. Baltimore City enforces the Building, Fire, and Related Codes of Baltimore City, 2024 edition.

The city publishes a list of work that is exempt from permit. If your job is not on that list, plan on a permit. Checked against the city's Work Exempt From Permit document and its permit pages in August 2026.

Almost always needs a permit

• Any addition, or enlarging the building in any direction.
• Removing or altering a load bearing wall, or any other structural change.
• Cutting a new window or door opening, including an egress window.
• Interior demolition, and exterior demolition.
• Finishing a basement.
• Building a deck, which gets a footing inspection and a final inspection.
• Building a fence, which gets a footing inspection as needed and a final.
• Installing or replacing electrical, gas, mechanical, HVAC and refrigeration, or plumbing systems.
• Changing the use of a building or of the land.
• Grading or excavating.
• Razing a building or moving one. The applicant has to be the owner.
• Formstone or paint removal, underpinning, and retaining walls. The applicant has to be the licensed contractor doing the work.
• Any exterior work on a property in a city historic district or on a local Landmark, including some work that would otherwise be exempt.

Usually needs one, because the exemption is narrower than it sounds

• Replacing a water heater. The exemption covers replacing a minor part, not a whole appliance.
• Replacing a furnace, boiler, air conditioner or heat pump, for the same reason.
• A kitchen or bathroom remodel where a fixture moves, or where wiring, piping, gas or ductwork is added, moved or replaced.
• Any electrical work beyond changing a lamp or plugging in portable equipment.
• Roof work that touches framing, structure or the shape of the roof.

Usually does not need a building permit

• Interior painting, papering, tiling, carpeting, cabinets, counter tops and similar interior finish work.
• Minor repair or patching of drywall or plaster.
• Replacing roof shingles, and replacing roof tarring.
• A one story detached shed, playhouse or similar accessory structure of 120 square feet or less. Zoning approval may still apply.
• A prefabricated swimming pool less than 24 inches deep, and playground equipment. Zoning approval may still apply.
• Boarding exterior openings with plywood, and removing debris other than as part of demolition.

A kitchen or bathroom remodel that only swaps finishes, cabinets and counter tops, without touching wiring, piping, gas or structure, sits in that last group. The moment a fixture moves or a system is altered, trade permits apply.

Ask the city before you assume

• Plumbing work at a house. The city's exempt list prints plumbing exemptions only under the heading for buildings other than one and two family dwellings, so do not assume any plumbing work at your house is exempt.
• Replacing a window in the existing opening at the same size. It is not on the exempt list and no city page answers it either way. Cutting a new or larger opening is an alteration and needs a permit.
• Installing or replacing siding. Not on the exempt list and not addressed elsewhere.
• Driveways, aprons and curb cuts. The permits office handles the building side and the Department of Transportation handles anything in the public right of way. Ask both.

The county answers job by job and sets numeric thresholds rather than publishing one exempt list. Checked against the county's published permit application pages in August 2026.

Needs a permit

• Any addition, alteration or structural modification to an existing dwelling.
• Creating a new bedroom or a new kitchen inside an existing dwelling.
• Weatherproofing or enclosing an existing porch or deck. The county treats it as an addition, so the same setback limits as the house apply.
• A deck more than 16 inches above the lowest grade, or a deck over 120 square feet.
• A shed, gazebo or garage greater than 120 square feet, for which the county states an MHIC licensed contractor must be used.
• A fence 42 inches or taller measured from the ground, including a fence sitting on a wall. The trigger is 42 inches, not the six feet repeated on non-county websites.
• Any in ground pool, plus a fence built to code. Above ground pools over 250 square feet with water 24 inches deep or more.
• Roof work where 50 percent or more of the sheathing or deck is being replaced.
• All electrical work, including extending circuit wiring, low voltage wiring, and connecting replacement equipment to existing wiring.
• All plumbing and gasfitting work.

Usually does not need a building permit

• A residential bathroom remodel. Plumbing and electrical permits are still always required for it, and the licensed plumber and electrician each apply for their own.
• Ordinary maintenance of existing electrical systems, such as replacing light fixtures and switches.
• Putting a second layer of shingles on a roof.
• Siding, unless the property is in a proposed or designated Historic District or on the Landmarks List.

Ask the county before you assume

• Roof repair below the 50 percent threshold. The county publishes two different answers on two different pages.
• Replacing windows or exterior doors like for like. The county publishes no page on it.
• A straight furnace, air conditioner or heat pump changeout with no new ductwork. What is settled is that connecting replacement equipment to existing wiring needs an electrical permit, and gasfitting work needs a gas permit.
• Finishing a basement. The rules on structural work and on creating a new bedroom would apply.
• Whether you can pull the permit yourself as the homeowner.

These are two different questions and they get mixed up constantly.

In Maryland, only an MHIC licensed contractor may contract with a homeowner to perform home improvement work, and home improvement is defined broadly: additions, alterations, remodeling, repair and replacement, plus work on the land around the house such as driveways, fences, garages, decks, porches and pools.

Pulling the permit is the contractor's job, not yours. Maryland regulation makes it the non-delegable duty of the prime contractor to secure every permit the job needs. Nobody can talk you into taking that off their shoulders. A permit for home improvement work carries the contractor's MHIC number, which makes the permit record itself a check on whether the licensed contractor named in your contract is the one who actually pulled it.

• In the city, an owner may apply, but the work still has to be done by the licensed party: MHIC for construction on one and two family dwellings, and licensed trades for electrical, mechanical, gas and plumbing.
• The city's own permit guidance states a homeowner cannot perform electrical, HVAC, gas or plumbing work.
• Demolition and moving permits in the city must be applied for by the owner.
• In the county, ask PAI directly whether you may pull a permit yourself for your situation. It depends on the work.

In Baltimore City, exterior work on a property inside a local historic district or designated as a local Landmark goes to CHAP, the Commission for Historical and Architectural Preservation, before the building permit is issued. CHAP sits in the Department of Planning rather than the permits office, so it is a second office and a second queue.

The city is blunt about the effect on your schedule: for properties in city historic districts, your permit will not be issued over the counter. CHAP approval comes first, in a document you will see called both an Authorization to Proceed and a Notice to Proceed.

The city states it in capitals: all permits require inspections. No Certificate of Occupancy is issued until every work permit has had its final inspection.

The published sequence

• New building or addition: footing, foundation, slab, framing, insulation, final.
• Alterations: framing, insulation, final.
• Decks: footing, then final. Fences: footing as needed, then final.
• Most electrical, mechanical, plumbing and HVAC permits need a rough-in inspection, and all of them need a final.

Each one has a moment it is called. Footings are inspected after excavation and once reinforcing steel is in place. Slabs and under-floor work are inspected before any concrete is placed or any sub-floor goes down. Framing is inspected after the roof deck, framing, fire blocking and bracing are in, everything that will be concealed is complete, and the rough electrical, plumbing, heating and ductwork have been approved.

Baltimore City publishes a target for the simplest permits: an application submitted by 9:00 am should be issued or answered by 2:00 pm the same business day, and one submitted later by 2:00 pm the next business day. Read that carefully. It is a target rather than a guarantee, it covers only the straightforward over the counter path, and it does not apply to anything routed to electronic plan review or to a referral such as CHAP, floodplain or design review. We checked it in August 2026 and you should confirm it before relying on it.

Baltimore County publishes no processing time, review turnaround or service level that we could find. We are not going to invent one. Call PAI and ask for a current estimate for your kind of job.

Permit fees in both jurisdictions are calculated from the scope and the value of the work, and they sit in schedules that get amended. We are not publishing figures that would be wrong within a year of writing. Ask the permit office for your job, or ask us and we will price the permit into the estimate.

One number worth knowing exists but is not printed here either: the city applies a surcharge to work begun or completed without a permit, to work beyond the scope of a permit, and to work done while a permit is suspended. It lives in Section 109 of the city code. The county states that working without an electrical permit is a violation subject to a civil penalty.

Doing the work first and permitting later is the most expensive way to run a renovation. Beyond the surcharge, the real cost arrives years later.

Unpermitted work surfaces when you sell or refinance. Lenders following Fannie Mae's rules require an appraiser who finds an addition without the required permit to address it, which can mean the work is not counted in the appraised value, or that the lender declines the file until it is resolved. Resolving it after the fact means opening finished walls so an inspector can see what is behind them.

Most of what gets renovated in Baltimore was built before 1978, so this is the normal case rather than the exception.

The federal Renovation, Repair and Painting rule applies to housing built before 1978. Anyone paid to do work that disturbs painted surfaces there has to work for an EPA certified firm with a certified renovator assigned to the job. The rule exempts minor repair disturbing six square feet or less of interior painted surface per room, or 20 square feet outside, but window replacement and demolition are never exempt at any size. Maryland does not run its own version, so the EPA enforces it here directly. We are EPA certified, NAT-F234904-1.

• The rule does not reach a homeowner doing the work themselves in their own home. It applies the moment they pay someone else.
• It does apply to a landlord doing the work personally in a rental unit.
• Lead abatement, meaning work whose purpose is to remove lead permanently, is a different legal category from renovation, with its own accreditation.
• Rental property in Maryland carries separate lead registration and risk reduction obligations. Confirm the current fee and renewal cycle with the Department of the Environment, because published sources describe them differently.

Whichever office you are calling, the conversation goes faster with these in front of you.

• The full property address, and certainty about whether it is in the city or the county.
• What you are actually doing, described in terms of what gets touched: walls moved, wiring added, a fixture relocated, a wall opened.
• The year the house was built.
• Whether the property is in a historic district, on a landmarks list, in a floodplain or in the Critical Area.
• Who will do the work, and their licence number.