Permit Required? Required
Typical Fee Range $150–$600 Residential rate is $10 per $1,000 of construction value; minimum fees apply.
Fee Method Valuation-based
Apply Online Apply at Inspectional Services Department →

What's Required in Boston

  • Structural drawings stamped by a MA Registered Professional Engineer.
  • Certified plot plan showing the deck's distance from property lines.
  • Footings must be at least 48 inches deep (frost line).
  • Railing height must be at least 36 inches for residential decks.
  • Stair treads must be at least 10 inches deep with 7.75-inch max rise.
  • Verification of joist hanger and ledger board fastening details.

When a Deck Needs a Permit in Boston

Whether a deck needs a building permit in Boston usually comes down to how high and how big it is. Low, ground-level platforms are often exempt, while raised decks need a permit — many cities draw the line at decks more than about 30 inches above grade (where guardrails and footings come into play), but Boston’s exact threshold is set by the Inspectional Services Department. 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 Boston

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 Boston. 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 Inspectional Services Department before starting; the requirements above outline what Boston expects.

How to Get a Deck Permit in Boston

1

Step 1: Design Review

Consult with an engineer to ensure the deck meets MA State Building Code.

2

Step 2: Zoning Clinic

Optional: Visit ISD to confirm your deck footprint doesn't violate lot coverage rules.

3

Step 3: Submit Long Form

Decks are considered structural and require a 'Long Form' permit application.

4

Step 4: Plan Audit

Building inspectors review structural loads and egress requirements.

5

Step 5: Inspection Chain

Requires inspections for footings, framing (before decking), and final completion.

Frequently Asked Questions

No, Boston zoning requires specific side and rear yard setbacks based on your district.
Yes, any raised wood structure attached to a dwelling requires a permit in Boston.
You may act as your own contractor for a 1-3 unit home, but you assume all liability for code compliance.
Usually not — swapping decking boards or railing on the same structure is generally considered maintenance in Boston. Replacing the framing (joists, beams, footings), rebuilding, or enlarging the deck typically does require a permit. Check the scope with the Inspectional Services Department.