Do I Need a Permit to Build a Shed in Boston, MA?

Interactive check

Check your shed details

Client-side only. No runtime backend required.

Project type City Shed size (sq ft) Stories Electrical work planned? Plumbing planned?

Fees

Estimated city fees

Baseline for a simple permitted shed: $250–$600 estimated combined fees (permit + plan review) for a permitted shed in Boston; sheds 200 sq ft and under with no utility work are generally building-permit-exempt under 780 CMR, but Boston Zoning Code setbacks and lot coverage rules still apply

Fee	Amount	Notes
Boston ISD building permit fee (sheds over 200 sq ft)	$175–$450 (estimated)	Boston ISD building permit fees for residential construction are based on project valuation. A typical residential shed ($5,000–$20,000 value) falls in this range. Verify current amounts with ISD at 1010 Massachusetts Avenue.
Plan review fee	$75–$150 (estimated)	A plan review fee is assessed for review of submitted construction drawings by ISD. Combined permit and plan review fees for a residential shed typically run $250–$600.
Electrical / plumbing / mechanical trade permits	$50–$200 each (estimated)	Each utility trade requires a separate Boston ISD permit and inspection, even when the shed itself is 200 sq ft or under and otherwise building-permit-exempt.
State building surcharge	$10–$25	Massachusetts assesses a state building surcharge on all permitted construction projects, collected by ISD.

Documents

Required documents

Boston ISD building permit application submitted in person at ISD offices at 1010 Massachusetts Avenue, Boston, MA 02118.
Scaled site plan showing property lines, existing structures, and the proposed shed location, footprint, dimensions, and distances to all property lines — required to confirm Boston Zoning Code setback, lot coverage, and rear-yard open-space compliance.
Floor plan and elevations showing shed dimensions, wall heights, roof pitch, door and window openings, and intended use.
Structural footing and framing details complying with 780 CMR 9th Edition, including footing depth below the 48-inch Massachusetts frost line, post/beam/rafter sizes, and connection hardware.
Construction Supervisor License (CSL) number for the supervising contractor, or Homeowner Exemption Affidavit if the homeowner personally supervises construction on an owner-occupied single- or two-family property.
Boston Landmarks Commission Certificate of Appropriateness if the shed is visible from a public way and the property is in a designated Boston Landmark District.
Manufacturer's installation instructions and specifications for prefabricated shed kits when applicable.
Trade drawings and load schedules for electrical, plumbing, or mechanical work if utilities are being added to the shed.

Timeline

Typical timing

Plan review: 5–15 business days for standard residential plan review
Total cycle: 4–8 weeks from application to final inspection for permitted sheds

Boston Landmarks Commission review (if required) can add 4–8 weeks before the ISD building permit application. Zoning variance proceedings (if the shed placement exceeds zoning limits) can add 2–4 months. Sheds within the 200 sq ft exemption with no utility work can proceed after confirming zoning setbacks, with no ISD plan review required.

Process

How the permit process works

Apply the 200-square-foot 780 CMR exemption as the first filter Under Massachusetts State Building Code 9th Edition (780 CMR) Section 107.2.1, a one-story detached accessory structure with a floor area of 200 square feet or less is generally exempt from the Boston ISD building permit requirement. Sheds over 200 sq ft, multi-story structures, and any shed with utility work require a permit. Note: Massachusetts's 200 sq ft threshold is more generous than California's 120 sq ft or Chicago's 100 sq ft. Even exempt-sized sheds must comply with Boston zoning requirements.
Verify Boston Zoning Code setbacks and lot coverage Use the City of Boston Zoning Viewer at bostonplans.org to identify the applicable zoning subdistrict and confirm the accessory structure setback, height limit, lot coverage maximum, and rear-yard open-space requirement. Boston residential zones have varying rules — an Allston triple-decker lot and a Jamaica Plain single-family lot may have different limits. Verify before ordering a prefab shed or pouring footings.
Screen for historic-district requirements Check whether the property is in a designated Boston Landmark District (Beacon Hill, Back Bay, Bay Village, South End, Charlestown Navy Yard, Fort Hill) using the Boston Landmarks Commission website at boston.gov/departments/landmarks-commission. If so, and if the shed would be visible from a public way, a Certificate of Appropriateness from the BLC must be obtained before applying for a building permit. The BLC reviews shed size, material, location, and visual impact from public streets.
Identify utility scope and trade permit needs Decide whether the shed will have electrical, plumbing, or mechanical work. Each utility trade requires a separate Boston ISD permit and inspection regardless of shed size. If you plan to add outlets, lighting, a subpanel, or plumbing to a 200-sq-ft-or-under shed, plan for trade permits even though the shed itself is building-permit-exempt.
Prepare 780 CMR-compliant drawings for permitted sheds For sheds over 200 sq ft, prepare a site plan, floor plan, elevations, and foundation details complying with Massachusetts State Building Code 9th Edition (780 CMR), based on the 2015 IRC with MA amendments. Footings must extend below the 48-inch Massachusetts frost depth. Include framing plan, rafter/truss details, and connection hardware. Prefab sheds should include manufacturer installation documents.
Apply in person at Boston ISD Submit the permit application and all required documents in person at Boston ISD, 1010 Massachusetts Avenue. Bring: permit application, site plan, floor plan, structural details, CSL information or Homeowner Exemption Affidavit, BLC Certificate if required, and payment. Boston ISD does not currently offer online residential building permit submission.
Pay fees and complete required inspections After plan review approval, pay the permit fee, plan review fee, and state surcharge. Post the permit card on-site before construction begins. Contact ISD to schedule required inspections — typically foundation/footing inspection before concrete pour, rough framing, and final. Trade inspections are scheduled separately.

Code basis

What Boston reviews against

Massachusetts State Building Code 9th Edition (780 CMR), based on the 2015 International Residential Code (IRC) with Massachusetts amendments — Section 107.2.1 (work exempt from permit: one-story detached accessory structures 200 sq ft or less); Boston Zoning Code (subdistrict-specific accessory structure regulations) for setbacks, height, and lot coverage; Massachusetts pool barrier requirements under 780 CMR / IBC Chapter 31. Boston enforces the Massachusetts Stretch Energy Code (Article 115.AA of 780 CMR) as a designated Green Community.

Residential permit page Boston permit portal

If you skip the permit

What can go wrong

Boston ISD can issue a stop-work order and require removal or correction of unpermitted shed construction that required a permit.
A shed placed in a required setback or exceeding lot coverage can be ordered relocated or removed through zoning enforcement.
After-the-fact Boston ISD review can require exposing foundation elements for inspection, adding significant cost.
Unpermitted electrical work in a shed creates fire and shock hazards that go unverified without ISD trade inspections.
Boston Landmarks Commission violations require separate historic preservation enforcement and can mandate restoration at the owner's expense.
Massachusetts law requires disclosure of known building code violations in residential real estate transactions — an unpermitted shed requiring a permit must be disclosed in a sale.

FAQ

Common Boston shed permit questions

Do I need a permit to build a shed in Boston, MA?

Usually not if the shed is 200 square feet or less. Under Massachusetts State Building Code 9th Edition (780 CMR) Section 107.2.1, a one-story detached accessory structure with a gross floor area of 200 square feet or less is generally exempt from the Boston ISD building permit requirement. Sheds over 200 sq ft and any shed with utility work require a permit. Note that Boston's 200 sq ft threshold is more permissive than the 120 sq ft limit in California — but Boston zoning setbacks and lot coverage rules still apply to all sheds.

What is the largest shed I can build without a permit in Boston?

The Massachusetts 780 CMR exemption threshold is 200 square feet for a one-story detached accessory structure. Boston ISD generally follows this state standard. However, the building-permit exemption does not mean zoning-exempt — Boston Zoning Code setbacks, lot coverage, height, and rear-yard open-space requirements still apply to any accessory structure, even exempt-sized sheds. Confirm zoning compliance using the Boston Zoning Viewer at bostonplans.org.

Does my Boston historic district affect shed permitting?

Yes. Properties in designated Boston Landmark Districts — Beacon Hill, Back Bay, Bay Village, South End, Charlestown Navy Yard, and Fort Hill — require a Certificate of Appropriateness from the Boston Landmarks Commission (BLC) before constructing a shed that is visible from a public way. This requirement applies regardless of the shed's size, even for structures under the building-permit threshold. Contact the BLC at boston.gov/departments/landmarks-commission before designing the shed.

What frost depth do I need for shed footings in Boston?

The Massachusetts frost depth is 48 inches. For permitted sheds requiring a building permit, footings must extend at least 48 inches below grade. Small exempt-sized sheds placed on concrete piers, deck blocks, or gravel pads are common but should be designed to minimize frost heave — consult a contractor familiar with Boston soil conditions.

Does adding electricity to my Boston shed require a permit?

Yes. Adding wiring, outlets, lighting, or a subpanel to a shed requires a separate Boston ISD electrical permit and inspection, even when the shed itself is 200 square feet or under and otherwise building-permit-exempt under 780 CMR.

How much does a shed permit cost in Boston?

For a shed requiring Boston ISD review, expect roughly $250–$600 in combined permit and plan review fees depending on size and scope. Sheds within the 200 sq ft exemption with no utility work incur no ISD building permit fee. Verify current amounts with Boston ISD at 1010 Massachusetts Avenue.

Sources

Official links and freshness

Related permits

More permits for Boston, MA

Related tools