Baltimore Deck Permit

What's Required in Baltimore

• Building permit required for decks greater than 16 inches above grade.
• Permit required for any deck exceeding 120 square feet.
• Site plan required for all decks under 600 square feet.
• Construction plans required for decks 600 square feet and over.
• Signed and sealed professional plans required for decks over 3,000 square feet.
• Always required if in a Historic District or floodplain.

When a Deck Needs a Permit in Baltimore

Whether a deck needs a building permit in Baltimore usually comes down to how high and how big it is. Low, ground-level platforms are often exempt, while raised decks need a permit — in Baltimore, the bar is unusually low: a deck more than 16 inches above grade needs a permit, and so does any deck over 120 square feet regardless of height. Attached decks almost always require a permit because they tie into the house’s structure, and even a freestanding deck usually needs one once it passes the size or height cutoff. Check the requirements above before you build, and note that zoning setbacks from property lines apply regardless.

Do You Need a Permit to Repair or Replace a Deck in Baltimore

It depends on how much you’re changing. Swapping worn decking boards or railing on the same layout is usually treated as maintenance and often doesn’t require a permit in Baltimore. But replacing the structural framing (joists, beams, posts, or footings), rebuilding the deck, enlarging it, or changing its height generally does — at that point it’s regulated like new construction. When in doubt, describe the scope to the Department of Permits, Approvals and Inspections before starting; the requirements above outline what Baltimore expects.

How to Get a Deck Permit in Baltimore

Frequently Asked Questions