ADU Rules in Scituate, MA
Yes. Scituate has allowed ADUs since 1989 and updated its bylaw in April 2025. The friction is not whether you can build. It is the two-tier sizing path, Site Plan Review, coastal flood rules in five named neighborhoods, septic capacity, and a short-term-rental prohibition recorded against your deed.
Call BuildX: (781) 627-7000
Scituate allows ADUs, and has since 1989
Town Meeting adoption: April 14, 2025 ATM · ADU regs since 1989Scituate has had ADU regulations since 1989, the longest-standing ADU program of any town in our South Shore research. Town Planner Karen Joseph confirmed the 1989 history at a December 2024 Select Board meeting [South Shore Times]. The town then ran a thorough update: public workshops December 11 and 12, 2024, a public hearing January 9, 2025 [Public Hearing], a February 26, 2025 draft [Zoning Bylaw], and adoption at the April 14, 2025 Annual Town Meeting, approved by the Attorney General on October 13, 2025 [Adopted 2025]. The result is a two-tier framework: ADUs up to 900 sq ft by Site Plan Review, and larger ADUs by Special Permit.
Can I build an ADU in Scituate, MA?
Yes. Scituate allows ADUs in single-family zones. An ADU up to 900 sq ft (or 50% of the principal dwelling, whichever is smaller) is by-right under state law and goes through procedural Site Plan Review by the Planning Board. A larger ADU, over 900 sq ft and up to 40% of the principal dwelling, requires a Special Permit. Short-term rental is prohibited and a restrictive covenant must be recorded before occupancy.
Show full bylaw framework, two-tier sizing, and state preemption note
Scituate's ADU provisions live in Section 530 (Accessory Dwellings) of the Zoning Bylaw, with Site Plan Review governed by Section 770. The framework was carried forward from the 1989 program and comprehensively updated at the April 14, 2025 Annual Town Meeting, approved by the Attorney General on October 13, 2025 [Zoning Bylaw]. The framework is explicitly two-tier, which is unusual on the South Shore:
- Tier A, up to 900 sq ft: ADUs at or under 900 sq ft (or 50% of the principal dwelling, whichever is smaller) are by-right under state law. The Planning Board runs Site Plan Review, which is procedural and cannot deny a protected-use ADU. [Zoning Bylaw] [760 CMR 71]
- Tier B, "Accessory dwellings, LARGE": ADUs over 900 sq ft, up to 40% of the principal dwelling, require a Special Permit from the Planning Board. Scituate is one of the few South Shore towns that explicitly allows larger ADUs this way. [Zoning Bylaw]
- Tier C, commercial structures: ADUs within structures used for businesses require a Special Permit. [Zoning Bylaw]
State preemption note. Scituate's pre-2025 rules required owner-occupancy with conditional yearly certifications. Massachusetts state law (760 CMR 71.00, effective February 2, 2025) preempts owner-occupancy requirements for protected-use ADUs [760 CMR 71], and the Affordable Homes Act amendment to MGL Chapter 40A enabled that preemption [MGL 40A]. Town Planner Karen Joseph acknowledged the change directly in December 2024 [South Shore Times]. In practice, the annual recertification and the owner-occupancy clause are no longer enforceable for a protected-use ADU. The two-tier sizing, the Site Plan Review step, and the short-term-rental prohibition all stand.
Karen Joseph also described the transition timeline in December 2024: applications received before February 2, 2025 were handled under the prior bylaw, and applications after that date follow state law. Confirm how Scituate is processing your application today with the Planning Department at (781) 545-8704 before you file.
Pre-2025 size range. Under the prior 1989 to 2024 rules, Scituate ADUs ranged from 430 to 1,520 sq ft, with certain districts allowing larger sizes by special permit, a wider range than most South Shore towns [South Shore Times]. The new two-tier framework keeps that flexibility while aligning the by-right tier with the 900 sq ft state cap.
Scituate also publishes an Approved Accessory Dwelling Units list [Approved ADUs]. In our experience reviewing ADU programs across the South Shore, that public permit tracking is unusual. The town tracks permits issued, so you can see the active ADU community before you start.
Scituate ADU Rules at a Glance
The six things most homeowners ask first. Tap "View all rule details" for the complete data set.
View all Scituate rule details
- ADU regulations first adopted: 1989 (longest-standing program in our South Shore research)
- Comprehensive update adopted: April 14, 2025 Annual Town Meeting; approved by the Attorney General October 13, 2025 [Adopted 2025]
- Bylaw location: Section 530, Accessory Dwellings (Site Plan Review under Section 770) [Zoning Bylaw]
- Tier A (by-right): Up to 900 sq ft or 50% of principal, Site Plan Review
- Tier B (Special Permit): Over 900 sq ft, up to 40% of principal dwelling
- Tier C (Special Permit): ADUs within commercial structures
- Owner-occupancy: Local clause preempted by 760 CMR 71.00
- Annual recertification: Preempted by 760 CMR 71.00
- Long-term rental: Allowed (31 days or more)
- Short-term rental: Prohibited per MGL c. 64G; restrictive covenant required
- Multiple principal dwellings: GFA of the largest principal dwelling is used for ADU size calculation
- Cottages: Not allowed as ADUs (Humarock and other cottage zones)
- Sewer status: Mixed. Town water; sewer in Scituate Harbor, downtown, parts of North Scituate; most outlying areas on septic
- WRPD overlay: Water Resource Protection District; additional review where it applies
- Coastal flood neighborhoods: Humarock, Sand Hills/North Scituate Beach, Scituate Harbor, Minot, Egypt Beach
- Demolition review threshold: Structures over 100 years old require Demolition Bylaw Review
- MBTA station: Greenbush Station in town (Greenbush Line)
- Permitting platform: Mandatory online since June 28, 2021 (no paper applications)
- Dimensional schedules: Vary by village subdistrict. Confirm exact setbacks, lot minimums, and height with the Scituate Planning Department at (781) 545-8704
Why BuildX Knows Scituate ADUs
Scituate is BuildX home territory. We work Scituate every month designing ADUs for your neighbors, and we know the village subdistricts, coastal flood neighborhoods, WRPD overlay, and the two-tier sizing path that drive your project.
We Work Scituate Every Month
Scituate is part of BuildX's South Shore home territory. We work Scituate every month designing ADUs for your neighbors. We bid Scituate ADU projects regularly as part of our standard business operations. We don't have a Scituate build on the board yet. Yours could be the first.
See One in Person
Walk through a real, finished BuildX ADU before you sign anything. Private showings are available by appointment.
Day 1 Property Review
Before quoting, we check zoning subdistrict, sewer or septic, FEMA flood zone, wetlands, WRPD overlay, and demolition-review status.
What We're Building Near Scituate
Scituate is BuildX home territory. We are your neighbors, not a regional contractor passing through. We don't have a Scituate build on the board yet, but we are building right next door.
Our nearby ADU projects: the Copeland ADU in Marshfield to the south is complete; the Williams ADU in Cohasset, which borders Scituate to the north, the Rainis ADU in Norwell just inland to the west, and the Morse ADU in Hanover are under construction; and the Derbes ADU, also in Marshfield, is in pre-construction. Across the South Shore, BuildX has an active pipeline of ADUs in roughly two dozen towns. The coast is home.
Real families. Real builds. Real ADUs on the South Shore. See more BuildX ADU builds →
What Can Complicate a Scituate ADU?
Scituate is a coastal town with five named flood-affected neighborhoods, multiple village subdistricts, and a Water Resource Protection District overlay. Your parcel's location and overlays, not the bylaw, are usually what move project cost and timeline. The factors that come up most often:
Which Scituate village subdistrict am I in? Zoning
Likely affects you if: your parcel is in or near Scituate Harbor, North Scituate Village, the Greenbush-Driftway Gateway, Humarock, or the VCN-GDG village neighborhood subdistricts.
Scituate has five or more village subdistricts, each with its own setback and use rules [Zoning Bylaw]: Scituate Harbor (Village Business Overlay District), North Scituate Village (VC and OV subdistricts), the Greenbush-Driftway Gateway, Humarock Village (Residential Overlay, with cottage zoning handled separately), and the VCN-GDG Village Center and Neighborhood subdistricts. This is the most subdistrict density of any town in our South Shore research.
Your ADU site plan must reference the correct subdistrict, and the dimensional rules differ between them. We pull the right subdistrict reference for your address on Day 1. Confirm the exact setbacks and dimensional requirements for your subdistrict with the Scituate Planning Department at (781) 545-8704.
What flood-zone rules affect Scituate ADUs? Coastal flood
Likely affects you if: your parcel is in Humarock, Sand Hills, North Scituate Beach, Scituate Harbor, Minot, Egypt Beach, or any other coastal or low-lying parcel mapped in a FEMA flood zone.
Scituate is one of the most flood-affected towns on the South Shore, with five named flood-exposed neighborhoods [FEMA]: Humarock (particularly vulnerable, frequent storm damage), Sand Hills and North Scituate Beach, Scituate Harbor, Minot, and Egypt Beach. These coastal areas fall in FEMA Velocity (V) and A flood zones; the exact zone is parcel-specific, so confirm your address against the FEMA Flood Map Service Center. ADU projects on these parcels are different projects.
Cost premium: 15% to 25% on top of base ADU cost for elevation, breakaway walls, and engineer-stamped flood compliance.
Design requirements: FEMA-compliant elevation above base flood elevation, breakaway lower-level walls in V-zones, engineer-stamped structural design, flood-resistant materials, and utility elevation.
Coastal storm advisories are routine in Scituate, so the Building Department processes flood-zone applications regularly. Engineer-stamped flood compliance is non-negotiable on the permit side.
Do I need septic approval for a Scituate ADU? Septic
Likely affects you if: your parcel is in one of Scituate's outlying neighborhoods rather than Scituate Harbor, downtown, or the sewered parts of North Scituate.
Scituate has town water plus limited sewer. Scituate Harbor, downtown, and parts of North Scituate are sewered; most outlying neighborhoods are on private septic. Adding a bedroom adds wastewater design flow, so a Title 5 inspection and capacity check are typically required before the ADU permit is approved on a septic-served lot [Title 5].
Cost impact: $30,000 to $60,000 for a Title 5 capacity check plus possible system replacement when an older system cannot carry an additional ADU bedroom, and a reserve area is required.
Confirm sewer availability for your specific address before design. Many outlying Scituate parcels will face Title 5 review; we pull septic records on the Day 1 property review.
How does the Scituate WRPD overlay affect ADUs? Water overlay
Likely affects you if: your parcel falls within Scituate's Water Resource Protection District or a Zone II wellhead recharge area.
Scituate's Water Resource Protection District (Zoning Bylaw Section 520) is a zoning overlay that protects municipal water sources drawn from the Scituate Reservoir and town wells [Zoning Bylaw] [MassGIS]. Properties in the WRPD face additional review for any new development, including ADU septic siting in Zone II recharge areas.
A MassGIS overlay check on Day 1 tells you whether your parcel sits within the WRPD or a Zone II recharge zone. We pull this before quoting, because it can add environmental engineering to the project.
Do wetlands or conservation rules affect Scituate ADUs? Wetlands
Likely affects you if: your lot is near a salt marsh, dune, the North River corridor, or any mapped wetland or pond.
Scituate has salt marshes, dunes, the North River corridor, and multiple ponds. The Scituate Conservation Commission administers wetlands review under the state Wetlands Protection Act (MGL c. 131 §40) plus the local Wetlands Bylaw [Conservation Commission] [Wetlands Act] [NSRWA]. Scituate is part of the North and South Rivers Watershed Association partnership, the same watershed work as Norwell, Pembroke, and Marshfield.
Adding an ADU near a wetland, salt marsh, dune, or the North River triggers a Notice of Intent or Request for Determination filing with the Conservation Commission. Plan on adding 6 to 10 weeks to the timeline if your parcel falls within a resource area or buffer.
Cost impact: +$5,000 to $15,000, plus 6 to 10 weeks of additional review.
Can my Humarock cottage become an ADU? Excluded
Likely affects you if: your property is in Humarock or another cottage-zoned beach area.
No. Beach cottages in Humarock and other cottage-zoned areas are not allowed as accessory dwelling units in Scituate [Zoning Bylaw]. This is a Scituate-specific exclusion: cottage zoning takes precedence over the ADU pathway.
If you are in a cottage zone, the ADU pathway is not available for converting the cottage. Talk to us about the alternatives that fit your parcel before you plan a build around a cottage conversion.
Do I need demolition review to convert an old structure? Historic
Likely affects you if: you are converting or removing a barn, carriage house, or other structure that is more than 100 years old.
Demolition of any Scituate structure over 100 years old requires a Demolition Bylaw Review determination [Demolition By-Law]. If you are considering converting a historic barn or carriage house to an ADU, or removing an old outbuilding to make room for a detached ADU, plan for this review step.
Scituate's 100-year threshold is more permissive than some neighbors, such as Marshfield's 75-year threshold, but it still adds time and design constraints when it applies. Confirm whether your structure triggers the review with the Building Department early.
Does Greenbush Station affect Scituate ADU parking? Transit
Likely affects you if: your parcel is near Greenbush Station or the Greenbush-Driftway Gateway subdistrict.
Unlike most South Shore towns, Scituate has an in-town commuter rail station: Greenbush Station on the MBTA Greenbush Line [MBTA]. The Greenbush-Driftway Gateway village subdistrict is specifically transit-adjacent.
Properties within 0.5 miles of Greenbush Station may be eligible for the state's transit-adjacent parking exemption under MBTA Communities Act provisions, which can reduce required off-street parking for an ADU. Worth checking your parcel's distance via MassGIS if you are near the station. Confirm how Scituate is applying its parking rules for your address with the Planning Department.
What Does a Scituate ADU Cost?
A Scituate ADU should not be priced from square footage alone. Two 800 sq ft ADUs can price very differently depending on coastal flood elevation, septic capacity, WRPD overlap, conservation review, the Special Permit path for larger ADUs, and site access.
That is the full span of our 14 floor plans. Prices include the complete building package, foundation through move-in-ready finishes. Site work is priced separately after a lot evaluation.
Scituate-specific cost premium factors
See full ADU pricing and floor plans. For a Scituate-specific quote, call (781) 627-7000. We will not quote a Scituate ADU until we know your village subdistrict, sewer or septic status, flood zone, and WRPD overlay status.
How the Scituate ADU Permit Process Works
The path depends on size. Tier A ADUs are by-right with procedural Site Plan Review. Tier B larger ADUs need a Special Permit. Everything goes through the mandatory online system.
-
1
Parcel and subdistrict review
1 to 2 weeks
BuildX maps your parcel against the correct village subdistrict, sewer or septic status, FEMA flood zone, wetlands and salt marsh resource areas, WRPD overlay, and demolition-review status before quoting. This step determines whether the rest of the timeline is straightforward or extended. MassGIS and parcel overlay checks happen on Day 1.
-
2
Tier A: Site Plan Review (by-right ADUs up to 900 sq ft)
Procedural Planning Board review, typically adds 30 to 60 days
For an ADU at or under 900 sq ft, the Planning Board runs Site Plan Review [Zoning Bylaw] [760 CMR 71]. This is procedural for a protected-use ADU, so the board cannot deny it, but the review still adds time. Coordinate with the Planning Department at (781) 545-8704.
-
3
Tier B: Special Permit (larger ADUs over 900 sq ft)
Add time for the public hearing, typically 60 to 120 days
For a "LARGE" ADU over 900 sq ft and up to 40% of the principal dwelling, the Planning Board requires a Special Permit [Zoning Bylaw]. This adds a public hearing to the timeline. Tier C ADUs within commercial structures also require a Special Permit.
-
4
Building permit and restrictive covenant
Submitted online; covenant recorded before occupancy
Submit the building permit through the electronic permitting system. A restrictive covenant prohibiting short-term rental must be recorded against the property at the Plymouth County Registry of Deeds prior to any occupancy [Plymouth Deeds].
-
5
Overlay reviews (if triggered)
Add 6 to 10 weeks (Conservation) or 30 to 90 days (demolition) when triggered
Title 5 septic review (MassDEP 310 CMR 15.000), Conservation Commission filings for salt marsh, dune, North River, and wetland buffers (MGL c. 131 §40), WRPD environmental engineering, FEMA flood compliance and engineer stamps for coastal parcels, and Demolition Bylaw Review for structures over 100 years old. These run alongside the permit but can extend the critical path.
Overall planning assumption: a clean Tier A parcel with no overlay triggers moves through Site Plan Review and permitting in a few months. A Tier B Special Permit, coastal flood compliance, septic upgrade, or Conservation filing each add to that. We map the critical path on the Day 1 property review.
After permits issue, construction inspections run through the Scituate Building Department. Confirm current administrative posture at (781) 545-8716.
What Scituate Zoning Districts Allow ADUs?
Scituate allows ADUs in single-family zoning districts, but it layers five or more village subdistricts over its traditional zoning, and each has different setback and use rules. Your ADU site plan must reference the correct subdistrict. The dimensional schedules vary by subdistrict; confirm the exact figures for your address with the Scituate Planning Department at (781) 545-8704.
Village subdistricts. Each has different rules. Most subdistrict density in our research
Scituate has five or more village subdistricts overlapping its traditional zoning [Zoning Bylaw]. Your ADU's setbacks, height, and use rules depend on which one your parcel sits in.
- Scituate Harbor: Village Business Overlay District. Commercial harbor village; some areas sewered.
- North Scituate Village: VC and OV subdistricts. Village Center mix.
- Greenbush-Driftway Gateway: Transit-adjacent gateway subdistricts near Greenbush Station.
- Humarock Village: Residential Overlay District. Cottage zoning is handled separately, and cottages are not allowed as ADUs.
- VCN-GDG: Village Center and Neighborhood District subdistricts. Multi-use village neighborhood.
What this means for your ADU: pull your subdistrict reference on Day 1. The same ADU design can need different setbacks in different subdistricts. We confirm the controlling subdistrict for your address before design, and defer the exact dimensional figures to the Planning Department.
Single-family residential districts
ADU rules: ADUs are allowed in Scituate's single-family zoning districts. An ADU up to 900 sq ft (or 50% of the principal dwelling, whichever is smaller) is by-right under state law and goes through procedural Site Plan Review. A larger ADU, over 900 sq ft and up to 40% of the principal dwelling, requires a Special Permit [Zoning Bylaw].
Multiple principal dwellings: if your lot has more than one principal dwelling, the GFA of the largest principal dwelling is used for the ADU size calculation [Zoning Bylaw].
What this means for your ADU: the size cap and permit path are clear, but the lot-level setbacks and coverage depend on your subdistrict and any overlay (WRPD, flood, wetlands). Confirm the exact dimensional values with the Scituate Planning Department at (781) 545-8704.
Overlay districts. WRPD, flood, wetlands.
The Water Resource Protection District (WRPD) protects municipal water sources and adds review for parcels in Zone II recharge areas. FEMA floodplain mapping affects the five named coastal neighborhoods. The local Wetlands Bylaw and state Wetlands Protection Act govern salt marsh, dune, North River, and pond buffers. Overlays modify, but do not prevent, ADU construction.
Overlay analysis happens on Day 1 with MassGIS layers. We pull your parcel's overlays before quoting.
Sewer or Septic? Scituate Is Mixed.
This is one of the biggest cost variables in any Scituate ADU project. Scituate has town water from the Scituate Reservoir and wells. Sewer covers Scituate Harbor, downtown, and parts of North Scituate. Most outlying neighborhoods are on private septic.
Show Title 5, water, sewer, and WRPD details
- Water Department: Scituate Water Department, (781) 545-8735. Scituate Reservoir plus wells.
- Sewer Department: Scituate Sewer Department, (781) 545-8736. A separate department, which not all towns have.
- Septic upgrade cost: $30,000 to $60,000 typical, plus a required reserve area
- Title 5 trigger: Adding a bedroom adds design flow, so Title 5 inspection is required on septic parcels [Title 5]
- WRPD overlay: Water Resource Protection District adds review in Zone II recharge areas [MassGIS]
- Septic program: WaterSmart South Shore SepticSmart program with NSRWA [NSRWA]
Sewer covers parts of Scituate; most outlying neighborhoods are on septic. We do not quote a Scituate ADU until we know which side of that line your parcel sits on. Confirm sewer availability for your specific address with the Sewer Department at (781) 545-8736; a Title 5 inspection answers the capacity question for septic-served lots.
Scituate Is a Coastal Town of Distinct Villages
Scituate's named areas have their own sewer status, flood-risk profile, and design context. A Humarock ADU is a different project from a North Scituate Village ADU. Five neighborhoods sit in named FEMA flood zones.
Scituate ADU Feasibility by Area (At a Glance)
| Scituate Area | Common ADU Issue | BuildX Note |
|---|---|---|
| Scituate Harbor | Village Business Overlay, coastal flood, some sewer | Subdistrict rules and flood profile drive design decisions |
| North Scituate Village | VC and OV subdistricts, mixed services | Pull the correct subdistrict reference before design |
| Greenbush | MBTA station vicinity, gateway subdistrict | Possible transit parking exemption near the station |
| Humarock | Cottage zoning, FEMA Zone V, frequent storm damage | Cottages are not allowed as ADUs; flood compliance required |
| Sand Hills / North Scituate Beach | Coastal Zone V, septic | Elevation and FEMA flood rules drive cost |
| Minot / Egypt Beach | Coastal Zone V, septic | Engineer-stamped flood compliance non-negotiable |
Scituate Harbor Some sewer Coastal flood
Commercial harbor village under the Village Business Overlay District. Some areas sewered. FEMA Zone V and A along the harbor.
Flood risk: High. Cost premium 15% to 25% on flood parcels.
North Scituate Village Mixed
Village Center mix across the VC and OV subdistricts. Pull the controlling subdistrict reference for your parcel before design.
Flood risk: Varies by parcel.
Greenbush Transit
Greenbush-Driftway Gateway subdistrict near the in-town MBTA Greenbush Station. Parcels within 0.5 miles may be eligible for the transit-adjacent parking exemption.
Flood risk: Low to moderate.
Humarock Zone V Cottages excluded
Beach cottage village under a Residential Overlay District. Particularly vulnerable to storms, FEMA Zone V. Cottages are not allowed as ADUs here.
Flood risk: Very high. Cost premium 15% to 25%.
Sand Hills / North Scituate Beach Septic Zone V
Coastal residential, FEMA Zone V. Elevation and flood-resistant design required.
Flood risk: High. Cost premium 15% to 25%.
Minot / Egypt Beach Septic Zone V
Coastal residential, FEMA Zone V. Engineer-stamped flood compliance and elevation requirements.
Flood risk: High. Cost premium 15% to 25%.
What Scituate's Town Planner Says
When the named Town Planner explains the bylaw transition on the public record, that is the operating posture homeowners should plan around.
Town counsel has advised us that everything that we get between now and February 2nd, we use the current zoning bylaw
Karen Joseph also confirmed that Scituate's prior bylaw required owner occupancy with conditional yearly certifications, a requirement now preempted by state law (760 CMR 71.00) for protected-use ADUs [760 CMR 71]. Applications received before February 2, 2025 were handled under the prior bylaw; applications after that date follow state law and then the updated bylaw adopted in April 2025. Confirm how Scituate is processing your application today with the Planning Department at (781) 545-8704.
Scituate Building Department
Scituate Building and Inspections Department
- AddressScituate Town Hall, 600 Chief Justice Cushing Highway, Scituate, MA 02066
- Building and Inspections(781) 545-8716
- Planning and Development(781) 545-8704 (Site Plan Review and Special Permit; Town Planner Karen Joseph [Planning Dept] [South Shore Times])
- Other departmentsBoard of Health (781) 545-8725 · Water Department (781) 545-8735 · Sewer Department (781) 545-8736
- Online permittingMandatory online since June 28, 2021. No paper applications accepted [Online permitting].
- Building Departmentscituatema.gov/buildinginspections-department
- Approved ADU listscituatema.gov/planning-board/pages/approved-accessory-dwelling-units
Scituate runs all permits through its electronic permitting system and publishes an Approved Accessory Dwelling Units list of permits issued [Approved ADUs]. The Building Department and Planning Department are separate; Site Plan Review and Special Permit applications go to Planning.
Questions to ask when you call Scituate
- The April 14, 2025 ADU bylaw received Attorney General approval on October 13, 2025; is the town now applying that adopted version to new ADU applications?
- Which village subdistrict is my parcel in, and what setbacks apply?
- Is my ADU a Tier A (Site Plan Review) or Tier B (Special Permit) project based on size?
- Is my property sewered or on septic, and will Title 5 review be required?
- Is my parcel in a FEMA flood zone, the WRPD, or a wetland or salt marsh buffer?
- Does my structure trigger the 100-year Demolition Bylaw Review?
- What is the current process for recording the short-term-rental restrictive covenant?
Explore Scituate ADU Topics
Jump to deep-dive sections on this page.
Scituate ADU FAQs
How big can my Scituate ADU be?
Up to 900 square feet, or 50% of the principal dwelling's gross floor area, whichever is smaller, on the by-right Tier A path with procedural Site Plan Review. Larger is possible: Scituate's Tier B "Accessory dwellings, LARGE" allows ADUs over 900 sq ft, up to 40% of the principal dwelling, by Special Permit. Scituate is one of the few South Shore towns that explicitly allows larger ADUs this way.
Do I need a Special Permit?
Not for a Tier A ADU at or under 900 sq ft. Those are by-right under state law and go through procedural Site Plan Review, which the Planning Board cannot deny for a protected-use ADU. You do need a Special Permit for a Tier B ADU over 900 sq ft (up to 40% of the principal dwelling), and for a Tier C ADU within a commercial structure.
Do I need to live there?
Scituate's prior bylaw required owner occupancy with annual certification, but state law (760 CMR 71.00, effective February 2, 2025) preempts owner-occupancy requirements for protected-use ADUs. Town Planner Karen Joseph acknowledged this preemption in December 2024. In practice, you may rent the principal dwelling and live in the ADU, or live in the principal dwelling and rent the ADU. Confirm the current operating posture with the Scituate Planning Department at (781) 545-8704 before signing a lease.
Can I Airbnb my Scituate ADU?
No. Scituate explicitly prohibits short-term rentals, defined per MGL c. 64G as periods of occupancy of 31 days or less [Zoning Bylaw] [MGL 64G]. A restrictive covenant prohibiting STR must be recorded against the property at the Plymouth County Registry of Deeds before any occupancy [Plymouth Deeds]. If your business case is Airbnb income, Scituate is firm; choose a different town. Long-term rentals of 31 days or more are allowed.
Can my Humarock cottage become an ADU?
No. Beach cottages in Humarock and other cottage-zoned areas are not allowed as accessory dwelling units in Scituate. Cottage zoning takes precedence over the ADU pathway. If you are in a cottage zone, talk to us about the alternatives that fit your parcel.
What if I am in a flood zone?
Possible, with engineer-stamped flood compliance. Scituate has five named flood neighborhoods: Humarock, Sand Hills and North Scituate Beach, Scituate Harbor, Minot, and Egypt Beach. A flood-zone ADU needs FEMA-compliant elevation, breakaway walls in V-zones, and engineer-stamped structural design, which adds 15% to 25% to the build. The Building Department processes flood-zone applications routinely.
Will I need to record a covenant?
Yes. A restrictive covenant prohibiting short-term rental must be recorded against the property at the Plymouth County Registry of Deeds before any occupancy. Budget roughly $500 to $1,500 in legal fees for the deed encumbrance. This is the same enforcement mechanism Norwell uses.
What does a Scituate ADU cost?
BuildX ADU pricing ranges from $284,301 to $525,861. That covers the complete building package, foundation through move-in-ready finishes; site work is priced separately after a lot evaluation. Scituate-specific drivers move a project within and beyond that band: coastal flood-zone parcels (Humarock, Sand Hills, Scituate Harbor, Minot, Egypt Beach) add 15% to 25% for elevation, breakaway walls, and engineer stamps. Septic upgrades add $30,000 to $60,000. A Tier B Special Permit, a WRPD overlay, or a Conservation filing each add time and cost. For a property-specific quote, call (781) 627-7000.
Who do I call about building an ADU in Scituate?
For building permits, inspections, and code questions, call the Scituate Building and Inspections Department at (781) 545-8716. For Site Plan Review, Special Permits, subdistrict questions, and the ADU bylaw, call the Planning and Development Department at (781) 545-8704.
For parcel-level feasibility, cost estimates, design options, subdistrict-specific considerations, and construction planning, call BuildX at (781) 627-7000.
The two are different conversations. The town can tell you what is administratively required. BuildX can tell you what is realistic on your specific parcel and what it will actually cost to build.
Sources Reviewed
Last verified: September 12, 2026. Grouped by source type so you can see which claims come from town law, state law, town process, local constraints, and media records.
View all 24 sources, grouped
- Town of Scituate. Building and Inspections Department. Town Hall, 600 Chief Justice Cushing Highway; (781) 545-8716.
- Town of Scituate. Online Permit Application. Mandatory online permitting since June 28, 2021.
- Town of Scituate. Planning and Development Department. (781) 545-8704. Site Plan Review and Special Permit authority.
- Town of Scituate. Planning Board FAQ: How do I add an Accessory Dwelling to my house?
- Town of Scituate. ADU bylaw revision document (December 11, 2024). Pre-final draft.
- Town of Scituate. Zoning Bylaw (October 2025, including the April 14, 2025 Annual Town Meeting changes; approved by the Attorney General October 13, 2025). Primary regulatory source: Section 530 Accessory Dwellings (two-tier sizing), Section 770 Site Plan Review, Section 520 Water Resource Protection District, and Sections 560, 570, and 580 village subdistricts.
- Town of Scituate. Public Hearing Notice (January 9, 2025). Planning Board hearing on proposed ADU zoning changes.
- Town of Scituate Planning Board. Approved Accessory Dwelling Units. Town's published list of ADU permits issued.
- Town of Scituate Historical Commission. Demolition Review By-Law. Demolition Permit Review by the Historical Commission for any building 100 years of age or older; 12-month delay for a preferably-preserved building (FEMA Velocity-Zone buildings exempt).
- Town of Scituate Planning Board. Approved Zoning Bylaw, 2025 Town Meeting. Adoption of the revised Zoning Bylaw by majority voice vote at the April 14, 2025 Annual Town Meeting; Attorney General approval October 13, 2025.
- Commonwealth of Massachusetts. Accessory Dwelling Units (760 CMR 71.00). Effective February 2, 2025; preempts Scituate's pre-2025 owner-occupancy and recertification requirements for protected-use ADUs.
- Massachusetts General Laws. Chapter 40A, Section 3. Zoning Act as amended by the Affordable Homes Act (Chapter 150 of the Acts of 2024).
- MassDEP. Title 5 (310 CMR 15.000) Compliance for ADUs FAQ. Relevant for Scituate's septic-served properties.
- Massachusetts General Laws. Chapter 64G (Short-Term Rentals). Defines a short-term rental as periods of occupancy of 31 days or less.
- Massachusetts General Laws. Chapter 131, Section 40 (Wetlands Protection Act).
- Scituate Conservation Commission. Wetlands, salt marsh, dune, and North River resource-area filings (Notice of Intent and Request for Determination). Contact via Scituate Town Hall.
- Wikipedia / U.S. Census 2020. Scituate, Massachusetts. Coastal town since 1633; multiple villages; population context.
- Census Reporter. Scituate Town Profile. Demographics (population near 19,000).
- Plymouth County Registry of Deeds. Plymouth County Registry of Deeds. Recording of the short-term-rental restrictive covenant.
- MBTA. Greenbush Line. Greenbush Station, an in-town commuter rail station; MBTA Communities adjacency.
- MassGIS, Bureau of Geographic Information. Aquifer and Zone II Wellhead Protection GIS layers. Water Resource Protection District context.
- Federal Emergency Management Agency. National Flood Hazard Layer / Flood Map Service Center. Scituate flood zones: Humarock, Sand Hills/North Scituate Beach, Scituate Harbor, Minot, Egypt Beach.
- North and South Rivers Watershed Association (NSRWA). North River corridor watershed partnership shared with Norwell, Pembroke, and Marshfield.
- South Shore Times. Scituate updates Accessory Dwelling Unit regs ahead of deadline. December 2024. Documents Town Planner Karen Joseph's December 2024 Select Board meeting remarks on owner-occupancy preemption and the transition timeline, and the 1989 ADU history.
Nearby South Shore ADU Rules
Scituate borders Cohasset to the north and Marshfield to the south along the coast, Norwell inland to the west, and sits near Hingham and Hanover. All are home territory for BuildX, the same neighborhoods we build in.
ADU Rules by City in the BuildX Service Area
BuildX serves 40 towns across four areas of southeastern Massachusetts. Each city has its own ADU bylaw, sewer or septic split, overlay map, and Building Department contact. Jump to the rules for your town:
South Shore (22)
South Coast (9)
Bridgewater Area (5)
Thinking about an ADU in Scituate?
BuildX can review your Scituate parcel for village subdistrict, sewer or septic, FEMA flood zone, wetlands, WRPD overlay, and demolition-review issues before you spend money on design or permitting. Scituate is BuildX home territory, so we know the constraints that drive your project and the two-tier path through Site Plan Review or a Special Permit.
See our ADU project portfolio or visit the ADU Home TourDisclaimer: The information on this page is drawn from live interviews, podcast episodes, municipal bylaws, planning board materials, town websites, and other publicly available sources, and reflects what was accurate as of the original recording or verification date. Pricing, timelines, materials, regulations, zoning rules, permit processes, fees, and overlay district boundaries can change -- sometimes without public notice -- and no two towns interpret or apply the rules the same way. This page is for informational purposes only and should not be relied upon as the basis for any purchasing, construction, or investment decision. BuildX makes no guarantee that the information is current or complete for your specific parcel. Before making any decisions, contact the town directly or call BuildX at (781) 627-7000 or schedule a Project Clarity Call to review your specific situation.