Plymouth County, MA Fence Regulations: Retaining Walls (2026)
Key Facts
- County Permit
- None; towns handle it
- Permit Exempt
- Up to 4 ft high
- Surcharged Wall
- Permit required
- Wetlands
- Conservation review common
Summary
No county permits retaining walls. Under the state building code, 780 CMR, a retaining wall up to four feet high, measured from the footing, needs no building permit unless it supports a surcharge. Taller or loaded walls require a town permit.
Retaining walls that are not over 4 feet (1219 mm) in height measured from the bottom of the footing to the top of the wall, unless supporting a surcharge.
Full Breakdown
Retaining walls follow the statewide building code, 780 CMR, applied by each town's building department, never the county. The code exempts a retaining wall not over four feet high, measured from the bottom of the footing to the top of the wall, from a building permit, unless the wall supports a surcharge such as a driveway or slope above it. A wall over four feet, or any loaded wall, needs a town building permit and usually an engineer's design. On the South Shore, walls near wetlands or the coast also draw conservation-commission review.
Violations & Fines
Building a regulated retaining wall over four feet without a town permit violates the building code and can be ordered corrected. Walls that redirect drainage onto a neighbor invite a civil claim.
Frequently Asked Questions
Do I need a permit for a retaining wall?
Who issues the permit?
Sources & Official References
Other rules in Plymouth County
Compare Plymouth County to another location·View the Massachusetts fence regulations overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.