Accessory Dwellings: New Opportunities for Homeowners and for Newton

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On March 4, Will Cohen, author of the Accessory Dwelling Unit Guidebook and a senior planner from Boston, discussed the benefits, implementation, and future of accessory dwelling units (ADUs).

The new state law regarding accessory dwelling units went into effect in February. It paves the way for greater ADU adoption across the state. This law allows, by-right, ADUs up to 900 square feet within zoning districts that allow single-family homes. Cohen emphasized that this new law provides a baseline, and cities and towns can choose to allow more in their local ordinances.

Unlocking Potential: Benefits for Homeowners

Cohen noted the many advantages that ADUs offer individual homeowners, painting a compelling picture of the opportunities they present:

●      Financial Security and Income Generation: An ADU can provide a steady stream of revenue, helping homeowners to help with mortgage costs or property taxes. This income can be particularly valuable for seniors on a fixed income or families looking for extra financial breathing room.

●      Flexibility for Evolving Family Needs: ADUs offer flexibility in accommodating changing family dynamics. Cohen illustrated this with examples such as providing a private and comfortable living space for aging parents, allowing adult children to come back to Newton affordably, or offering independent living quarters for family members with disabilities. This adaptability ensures that homes can remain functional and supportive as family needs evolve over time.

●      Enabling Aging in Place: Many long-term residents desire to remain in their community as they age. ADUs can play a crucial role in facilitating this. Cohen pointed out that homeowners can downsize into a smaller, more manageable ADU on their property. This allows individuals to stay within their familiar surroundings, close to friends and support networks, without the burden of maintaining a large, potentially empty house.

●      Potential Increase in Property Value: While not the primary motivation for everyone, Cohen noted that adding a well-designed and permitted ADU can often increase a property's overall value. This added value can be a significant asset in the long run.

Strengthening the Fabric: Benefits for the Community

Beyond the individual homeowner, Cohen articulated the significant positive impacts that widespread ADU adoption can have on the broader community:

●      Supporting Multigenerational Living and Family Support Networks: The ability for families to live in close proximity while maintaining a degree of independence can provide invaluable support for childcare, eldercare, and overall family well-being.

●      ADUs Address the Changing Demographic Trends: Due to Massachusetts's aging population and the trend across the country toward smaller households, smaller homes are in demand. ADUs can help meet that need.

●      Contributing to Sustainable Land Use: Cohen highlighted that ADUs minimize sprawl and the need for new infrastructure by utilizing existing residential lots. Thus, they contribute to a more environmentally responsible development pattern. ADUs are a way of adding “gentle density” without teardowns.

●      More Affordable Homes Supports Local Businesses and the Workforce: The availability of more affordable housing options, facilitated by ADUs, can have a direct positive impact on local businesses and the workforce. If more people who worked in Newton could live here, it would be easier to hire and retain people for our local businesses, our schools, and other city services. Cohen noted that individuals who can afford to live closer to where they work are more likely to support local shops, restaurants, and services, contributing to a vibrant local economy.

●      Addressing the Housing Shortage: In a region grappling with a persistent housing shortage, ADUs offer a relatively efficient way to increase the overall housing stock. They utilize existing land and infrastructure, making them a more sustainable and less disruptive solution than large-scale developments. Every ADU created contributes to easing the pressure on the housing market.

Building Blocks: Different Types of ADUs

Cohen then provided a clear overview of the various ways ADUs can be constructed, offering concrete examples to illustrate the possibilities:

●      Internal Conversion ADUs: These involve repurposing existing space within the primary dwelling:

○      Inside an Existing Home: Convert part of your home into a separate unit with a kitchen, bathroom, and separate entrance.

○      Attic Apartments: Converting an attic space into a habitable apartment, often requiring the addition of dormers for adequate light and headroom.

○      Internal Garage Conversions: Converting an attached garage into living space.

●      Attached ADUs: These are additions to the primary dwelling:

○      Side or Rear Additions: Building a new living unit attached to the side or rear of the existing house, with its own entrance.

○      Above-Garage Apartments: Constructing a separate apartment above an existing attached or detached garage.

●      Detached ADUs: These are separate structures on the same property:

○      Backyard Cottages or Guest Houses: Small, standalone dwellings built in the backyard.

○      Converted Detached Garages or Carriage Houses: Transforming an existing building into a complete living unit.

A Roadmap for Homeowners: Boston's ADU Guidebook

Cohen highlighted the city of Boston’s commitment to facilitating ADU development by creating a comprehensive ADU Guidebook. This resource serves as a step-by-step guide for homeowners interested in exploring the possibility of building an ADU on their property. The guidebook covers everything from initial planning and design considerations to permitting processes and construction best practices, aiming to demystify the process and empower homeowners to confidently move forward.

Navigating the Rules

Cohen also discussed Boston's ongoing efforts to update its zoning regulations to accommodate ADUs better. He touched upon several key considerations being addressed in these updates:

●      Nonconformity: Addressing how ADUs can be integrated into properties that may have existing zoning nonconformities. (Many homes in Newton have existing nonconformities.)

●      Setbacks: Reviewing and potentially adjusting setback requirements.

●      Lot Coverage: Considering the impact of ADUs on overall lot coverage and finding appropriate balances.

●      Parking: Exploring parking requirements for ADUs, recognizing that many ADU residents may not require an additional parking space.

Cohen emphasized that the goal of these zoning updates is to create a clear and supportive regulatory framework that encourages the creation of ADUs while also respecting neighborhood character and ensuring public safety.

Funding the Vision: Financing Options for ADUs

A crucial aspect of ADU development is financing. Cohen briefly touched upon common financing methods available to homeowners, including:

●      Home Equity Lines of Credit (HELOCs): Utilizing the existing equity in your primary residence to fund the construction or conversion of an ADU.

●      Construction Loans: Obtaining specific loans designed for home renovation and construction projects.

●      Personal Savings: For some homeowners, utilizing their savings may be a viable option.

A Promising Path Forward: Conclusion

Will Cohen’s message was clear: ADUs offer significant benefits for individual homeowners and the broader community while addressing the region’s housing challenges. From providing financial security and flexibility for families to increasing housing stock and promoting economic diversity, the potential of ADUs is undeniable.