Waltham Zoning & Land Use Guide
Official references and local checks
Use the official references below to identify the rules that apply to your address, then confirm parcel-specific requirements with the local authority before filing an application.
Official references
- Population:
- 62,227
- County:
- Middlesex County
- State building code:
- MA State Building Code 10th Edition (based on 2021 IBC)(statewide default)
- State ADU law:
- Yes — Section 8 of Chapter 150 of the Acts of 2024 (the Affordable Homes Act) amends MGL Chapter 40A Section 3 to require municipalities to allow a single accessory dwelling unit by right in single-family residential zoning districts, prohibiting zoning ordinances from banning ADUs or requiring a special permit, though reasonable site-plan, dimensional, and short-term rental regulations remain allowed. The provisions took effect February 2, 2025. The 2020 MBTA Communities Act (Chapter 358) separately mandates multifamily-by-right zoning near transit.
- FEMA flood map:
- Search flood zones
- Planning department:
- City of Waltham Planning Department
- Municipal code:
- View code online
- Zoning map:
- View local zoning map
Before you apply
- Call the City of Waltham Planning Department: (781) 314-3380
- Search the municipal code for the chapter that covers your zoning district and proposed use.
- Use the local zoning map to look up your parcel's zoning designation before applying for a permit.
- Check FEMA flood zone for your parcel — flood-zone status changes setbacks, foundation requirements, and insurance.
- Check your HOA CC&Rs and recorded deed restrictions — they are common in Waltham and frequently restrict ADUs, fences, and exterior changes beyond what zoning allows.
Key Zoning Facts
Regulatory Layers That Apply in Waltham
Your property is subject to ALL of these regulatory layers. Each one can impose additional requirements beyond the others.
Federal
- FEMA flood mapping: check parcel-specific flood-zone status
- View FEMA Flood Map
State — Massachusetts
- Building Code: MA State Building Code (780 CMR, based on 2021 IBC)
- State ADU Override: Yes (MA ADU Law (2024) — requires single-family zones to allow ADUs by right)
County — Middlesex County
City / Municipal
The municipality's zoning ordinance, building-code enforcement, and local permits form the primary local layer of land-use regulation for your property.
Overlay Districts
No overlay districts identified.
Private Restrictions
- Private covenants, deed restrictions, condominium rules, or association rules can impose requirements beyond zoning.
- Check HOA CC&Rs for additional restrictions.
Statewide Context (Massachusetts)
Local data for Waltham is limited. The following state-level facts apply across Massachusetts and are inherited by this page until city-specific details are verified.
- State Building Code
- MA State Building Code 10th Edition (based on 2021 IBC)
- State ADU Preemption
- Yes — state law overrides local rules
- Coastal Zone
- Yes
- Wildfire Zones
- No
ADU Rules in Waltham
- Max Size
- 900 sq ft
- Max Height
- 20 ft
- Rear Setback
- 5 ft
- Side Setback
- 5 ft
- Parking
- No additional parking required
- Owner Occupancy
- Not required under state ADU law
- Permit Timeline
- 45-75 days
Permit Costs & Timelines
Check Current Permit Fees & Timelines
Permit fees and review times can vary by project type, scope, valuation, and required approvals. Check the current schedule with the local permitting authority before filing.
Check current Waltham permit information →Official Sources
City-specific