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§ 02
When a permit is required
Permit triggers and exempt work for Cambridge
A building permit is required prior to constructing, altering, repairing, or demolishing any structure.
Ordinary repairs to structures that do not affect structural elements, egress, fire protection systems, fire ratings, energy conservation, plumbing, gas, electrical, or other utilities
One-story detached accessory structures (tool sheds, playhouses, etc.) not exceeding 120 sq ft
Retaining walls not exceeding 4 feet in height measured from footing bottom to top
Water tanks on grade with capacity not exceeding 5,000 gallons and height-to-diameter ratio not exceeding 2:1
Sidewalks and driveways not more than 30 inches above adjacent grade, not over basement space, and not on an accessible route
Painting, wallpapering, tiling, carpeting, and similar finish work
- Exempt Ordinary repairs to structures that do not affect structural elements, egress, fire protection systems, fire ratings, energy conservation, plumbing, gas, electrical, or other utilities
- Exempt One-story detached accessory structures (tool sheds, playhouses, etc.) not exceeding 120 sq ft
- Exempt Retaining walls not exceeding 4 feet in height measured from footing bottom to top
- Exempt Water tanks on grade with capacity not exceeding 5,000 gallons and height-to-diameter ratio not exceeding 2:1
- Exempt Sidewalks and driveways not more than 30 inches above adjacent grade, not over basement space, and not on an accessible route
- Exempt Painting, wallpapering, tiling, carpeting, and similar finish work
Note: Plumbing, electrical, and gas work within otherwise exempt projects may still require trade permits. Confirm all edge cases with the Inspectional Services Department.
Required documents
- Completed permit application
- Estimated Cost of Construction Affidavit
- Homeowner's Affidavit (if applicable)
- Contractor documentation (if applicable)
- Plans and supporting documents as required
- Building code
- 780 CMR 9th Edition (transitioning to 10th Edition effective July 1, 2025)
- Permit validity
- Work must commence within 6 months of permit issuance; work must be completed within 2 years (standard Massachusetts provision; verify with department).
- Owner-builder
- Owner-builders may act without a CSL for their own single-family residence.
- Contractor requirements
- All work must comply with 780 CMR. Licensed contractor (CSL) required; Home Improvement Contractor (HIC) registration additionally required for residential work on 1-4 unit owner-occupied properties.
§ 03
Application process
Typical processing: Not published; contact department at 617-349-6100 for current timelines.
- 01 Submit application through the OpenGov portal or in person at 831 Massachusetts Avenue.
- 02 Provide required affidavits (Estimated Cost of Construction Affidavit, Homeowner's Affidavit if applicable, or contractor documentation).
- 03 Application reviewed for completeness; plan review conducted where required.
- 04 Applicant notified of approval and invoiced for permit fees.
- 05 Pay fees; permit card issued.
- 06 Post permit card visibly at job site before work commences.
- 07 Schedule required inspections through the department.
Typical processing time: Not published; contact department at 617-349-6100 for current timelines.
§ 04
Fee schedule
Effective January 1, 2024
Fee type
Amount
01
Minimum permit fee
$50
02
Plan check fee
$100 included in the building permit fee
03
Permit fee formula
Residential (3 units or fewer): $15.00 per $1,000 of construction cost (or fraction thereof); Commercial / all other: $20.00 per $1,000 of construction cost (or fraction thereof)
04
Trade permit fee
Included in building permit
05
Reinspection fee
$25 to $100 depending on violation type
06
Penalty (no permit)
Triple the standard fee for work commenced without permit
Permit fees are invoiced after approval; payment is required before the permit is officially issued.
Fees change periodically. Confirm at the official fee schedule ↗ (effective January 1, 2024) before budgeting.
§ 05
Required inspections
Scheduling and sequence
How to schedule
- 617-349-6100 (phone)
- OpenGov portal (online)
- Scheduling deadline
- Contact department for scheduling.
- Inspection hours
- Monday 7:00 AM - 6:00 PM; Tuesday through Thursday 7:00 AM - 3:30 PM; Friday 7:00 AM - 12:00 PM
Typical sequence: Typical sequence for residential projects: Foundation / footing inspection (before pouring); Framing inspection (before insulation or wallboard); Insulation inspection (if applicable); Final building inspection. Trade inspections (electrical, plumbing, gas, mechanical) are coordinated separately with respective inspectors.
§ 06
Frequently asked
Common questions about Cambridge permits
01 Do I need a building permit in Cambridge, MA? ▸
A building permit is required prior to constructing, altering, repairing, or demolishing any structure.
02 How much does a building permit cost in Cambridge, MA? ▸
Building permit fees in Cambridge, MA are set by the local building department and vary by project type and valuation. The minimum permit fee is $50. Fees are calculated as: Residential (3 units or fewer): $15.00 per $1,000 of construction cost (or fraction thereof); Commercial / all other: $20.00 per $1,000 of construction cost (or fraction thereof). Plan check fee: $100 included in the building permit fee.
03 How do I apply for a building permit in Cambridge, MA? ▸
To apply for a building permit in Cambridge, MA, follow these steps: 1. Submit application through the OpenGov portal or in person at 831 Massachusetts Avenue. 2. Provide required affidavits (Estimated Cost of Construction Affidavit, Homeowner's Affidavit if applicable, or contractor documentation). 3. Application reviewed for completeness; plan review conducted where required. 4. Applicant notified of approval and invoiced for permit fees. 5. Pay fees; permit card issued. 6. Post permit card visibly at job site before work commences. 7. Schedule required inspections through the department.
04 How long does it take to get a building permit in Cambridge, MA? ▸
Building permit processing times in Cambridge, MA typically run Not published; contact department at 617-349-6100 for current timelines.. Timelines can vary based on project complexity and current department workload.
05 What work is exempt from building permits in Cambridge, MA? ▸
Not all construction work requires a permit in Cambridge, MA. The following work is generally exempt: Ordinary repairs to structures that do not affect structural elements, egress, fire protection systems, fire ratings, energy conservation, plumbing, gas, electrical, or other utilities; One-story detached accessory structures (tool sheds, playhouses, etc.) not exceeding 120 sq ft; Retaining walls not exceeding 4 feet in height measured from footing bottom to top; Water tanks on grade with capacity not exceeding 5,000 gallons and height-to-diameter ratio not exceeding 2:1; Sidewalks and driveways not more than 30 inches above adjacent grade, not over basement space, and not on an accessible route; Painting, wallpapering, tiling, carpeting, and similar finish work. Note: Plumbing, electrical, and gas work within otherwise exempt projects may still require trade permits. Confirm all edge cases with the Inspectional Services Department. When in doubt, confirm with the local building department before starting work.
06 How do I schedule a building inspection in Cambridge, MA? ▸
Once your permit is issued and work reaches an inspection milestone, you can schedule a building inspection in Cambridge, MA via: 617-349-6100, OpenGov portal. Contact department for scheduling..
last verified April 2026
source Inspectional Services Department ↗
entry id permits/massachusetts/middlesex/cambridge
Educational reference. Permit rules and fees change — confirm current requirements directly with Inspectional Services Department before applying. Jaspector is not legal advice.