Do I need a permit for interior work in Maryland?
Usually yes for anything structural, electrical, plumbing or mechanical, and usually no for finishes. Painting, flooring and replacing drywall on existing framing are ordinarily not permit work. Moving a wall, adding a circuit, relocating a drain or changing egress ordinarily is. The county decides, not the state, so the answer changes between Montgomery, Prince George and Charles.
The rule of thumb
If the work changes the structure, the systems, or the way people get out of the building in a fire, expect a permit. If it changes only the surface, usually not.
Replacing a vanity in the same place is ordinarily a finish job. Moving that vanity to the other wall involves the drain and the supply, so it is not.
Your county decides, not Maryland
Maryland does not run one permit desk. Each jurisdiction issues and inspects, with its own thresholds, fee schedules and turnaround times. Montgomery County, Prince George County and Charles County all handle this separately, and a project that needs a permit in one may be handled differently in another.
Historic districts add another layer, and so do homeowner associations, which are not government but can still stop work.
Basements are the one people get wrong
Finishing a basement is permit work in essentially every jurisdiction around here, because it creates habitable space. That brings in egress requirements, ceiling height, smoke and carbon monoxide detection, and the electrical work to serve the new rooms.
Adding a bedroom below grade without an egress window is the single most common problem we are called to correct, usually when the house is being sold and it comes up in the inspection.
What happens if it was never permitted
Unpermitted work tends to surface at the worst moment. At sale, when the buyer inspection finds it. At refinance, when the appraisal does not match the county record. At claim time, when an insurer asks whether the work was permitted.
It can usually be resolved afterwards, and it costs more and takes longer than doing it in order, because parts of it may have to be opened back up for inspection.
Who pulls it
We pull permits and manage the inspection schedule for the work we do. Be careful with any contractor who asks you to pull the permit as the homeowner on work they are performing, because that shifts responsibility for the work onto you.
Your city page names the office that issues permits for your jurisdiction. Requirements change, so treat this as the shape of it rather than the current rule and let us confirm for your specific scope.
The Work Behind This Answer
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