Wenham

• Wenham is transitioning from a special permit (Board of Appeals) requirement to by-right approval for ADUs, via a draft bylaw amendment as of February 2025.
• The draft replaces the old "Accessory Apartment" section (255-4.3B) with a new "Accessory Dwelling Unit" section aligned with state law.
• Maximum size is 900 sq ft or 50% of the principal dwelling, whichever is smaller. No bedroom or bathroom limits are specified in the draft.
• Short-term rentals are prohibited. Separate ownership is not allowed.
• Detached ADUs must comply with fire code CMR 527 1.00. Historic District compliance is required where applicable.

1. Prepare application: Standard building permit application demonstrating compliance with Section 255-4.3B (as amended) and all applicable zoning requirements.
2. Submit to Building Inspector: ADUs are now by-right; no Board of Appeals special permit is required.
3. Demonstrate dimensional compliance: Must meet all dimensional requirements in Article 5 of the Wenham Zoning Bylaw, except that Section 255-5.2G(1) does not apply to ADUs.
4. Fire code compliance (detached): If detached, demonstrate compliance with fire code CMR 527 1.00 regarding the unit's location relative to the primary dwelling.
5. Historic District review (if applicable): If the lot is in a Historic District, comply with applicable Historic District Bylaws or regulations.
6. Section 255-4.4C findings: Section 255-4.4C applies to ADUs, but findings do not require issuance of a special permit.

• Maximum size: 900 sq ft of gross floor area or 50% of the gross floor area of the principal dwelling, whichever is smaller.
• Foundation: Must have a permanent foundation; no trailers are permitted as an ADU.
• Attached ADU design: An attached ADU shall, to the extent possible, maintain the appearance of a single-family dwelling.
• Separate entrance: Must maintain a separate entrance, either directly from the outside or through a shared entry hall/corridor meeting building code egress requirements.
• House number: Must have its own house number visible from the exterior of the unit.
• Dimensional requirements: Must meet all dimensional requirements for lots and structures in Article 5, with the exception of Section 255-5.2G(1).

• Parking: One dedicated off-street parking space must be maintained for the ADU.
• Transit exemption: No parking space is required if the ADU is located within 0.5 miles of a commuter rail station or bus station.
• Curb cuts: No additional curb cut will be authorized for access to an ADU.

• Fire code (detached ADUs): If detached, the unit and its location relative to the primary dwelling must comply with fire code CMR 527 1.00. This is a notable local requirement not found in all municipalities.
• Historic District: If the lot is in a Historic District, the applicant must comply with all applicable Historic District Bylaws or regulations.
• Draft status: This bylaw is a draft amendment as of February 2025. It is pending Town Meeting vote. Until adopted, the previous "Accessory Apartment" rules technically remain in effect, but state law (760 CMR 71.00) preempts conflicting provisions.
• State regulation supremacy: The draft bylaw explicitly states that where there is any conflict between local definitions and those in 760 CMR 71.02, the state regulations control.
• Severability: The draft includes a severability clause -- if any part is held unconstitutional or invalid, the remainder survives.
• One ADU per lot: Only one ADU is permitted per lot.

Warrant Article

To see if the Town will vote to amend the Town of Wenham Zoning Bylaw as follows with language to be deleted in strikethrough and language to be added in italics and underlined except that existing Section 255-4.3B Accessory Apartment shall be struck in its entirety and replaced with a new Section 255-4.3B Accessory Dwelling Unit, or take any other action relative thereto:

I. Amend Section 255-2.2 Definitions

Old Definition (Deleted):

ACCESSORY APARTMENT: A separate dwelling unit within or as an attached portion of a single-family dwelling or within an accessory building subject to the provision of Section 255-4.3B.

New Definition:

ACCESSORY DWELLING UNIT or ADU: A self-contained housing unit, inclusive of sleeping, cooking, and sanitary facilities located on the same lot as a principal dwelling, subject to otherwise applicable dimensional and parking requirements, that, (1) maintains a separate entrance, either directly from the outside or through an entry hall or corridor shared with the principal dwelling sufficient to meet the requirements of the state building code for safe egress and (2) is not larger in gross floor area than 1/2 the gross floor area of the principal dwelling or 900 square feet, whichever is smaller.

II. Amend Article 4 Use Regulations

Section 255-4.1 Table of Use Regulations

Accessory:

BA = Board of Appeals special permit; Y = By right

Section 255-4.3B. Accessory Dwelling Unit

(Strike the entire existing section and replace with the following new section)

An Accessory Dwelling Unit shall:

(1) Meet all of the following requirements:

(a) All dimensional requirements for lots and structures set forth in Article 5 of this Bylaw along with all other applicable zoning requirements for the district in which it is located; provided however, that Section 255-5.2G(1) shall not apply to any ADU.

(b) One dedicated off-street parking space must be maintained for the ADU, unless the ADU is located within 0.5 miles from a commuter rail station, or bus station.

(c) May not be rented or occupied as a "short-term rental" as that term is defined in G.L. c.64G, Section 1.

(d) May not be maintained in separate ownership from the principal dwelling.

(e) If detached, the unit and its location to the primary dwelling shall be in compliance with the fire code CMR 527 1.00.

(f) Will have its own house number visible from the exterior of the unit.

(g) If the Lot is in an Historic District, the applicant shall comply with any applicable Historic District Bylaws or regulations.

(h) Must have a permanent foundation; no trailers will be permitted as an Accessory Dwelling Unit.

(i) An attached ADU shall to the extent possible maintain the appearance of a single-family dwelling.

(j) There shall be no more than one Accessory Dwelling Unit per Lot.

(k) No additional curb cut will be authorized for access to an Accessory Dwelling Unit.

(2) Section 255-4.4C shall apply to an ADU, provided, however, that to the extent a finding is required, such finding shall not require the issuance of a special permit.

(3) To the extent there is any conflict between definitions contained in this Bylaw and those contained in 760 CMR 71.02, 760 CMR 71.02 shall control.

(4) If any part of this Bylaw is for any reason held to be unconstitutional or invalid, such decision shall not affect the remainder of this Bylaw.

Wenham has adopted the Stretch Energy Code. A certified HERS Rater is required for all new construction, including ADUs.

Your ADU must achieve a HERS index of 52 or lower (mixed-fuel) or 55 or lower (all-electric). Going all-electric earns a 3-point offset, making compliance easier. Budget $500–$1,500 for HERS testing.

ERV/HRV mechanical ventilation is now required (bath fans alone don't qualify). If on-site parking is provided, EV-ready wiring is also required.

The following local provisions have been or will be preempted by the Massachusetts Affordable Homes Act (Chapter 150 of the Acts of 2024) and 760 CMR 71.00:

• Owner occupancy: Wenham's previous "Accessory Apartment" bylaw likely required owner occupancy. This is no longer permitted under state law. The draft bylaw removes any such requirement.
• Special permit: The previous bylaw required a Board of Appeals special permit (BA) for accessory apartments. State law mandates by-right approval. The draft bylaw changes from BA to Y (by right).
• Family member restrictions: Any previous restrictions limiting ADUs to family members are preempted by state law.
• Existing building restriction: The old "Accessory Apartment" definition limited units to within or attached to a single-family dwelling or accessory building. State law permits detached ADUs as well.

The draft bylaw explicitly acknowledges state supremacy: "To the extent there is any conflict between definitions contained in this Bylaw and those contained in 760 CMR 71.02, 760 CMR 71.02 shall control."

• Wenham Draft ADU Bylaw Amendment: https://www.wenhamma.gov/DocumentCenter/View/1602/Accessory-Dwelling-Unity-Proposed-Draft-Bylaw-Amendment
• Town of Wenham website: https://www.wenhamma.gov
• Massachusetts Affordable Homes Act (H.4977 / St. 2024, c. 150)
• 760 CMR 71.00 (Protected Use Accessory Dwelling Units)
• Fire Code CMR 527 1.00