Massachusetts now allows Accessory Dwelling Units (ADUs) under 900 square feet to be built by right in single-family zoning districts, thanks to recent legislation signed by Governor Healey. This change gives homeowners more flexibility to create rental units, accommodate extended family, or boost property value without the red tape of special permits.
At VIACAD, LLC, we design ADUs that align with the new legal standards while reflecting your goals, property constraints, and vision. From zoning analysis to final construction drawings, we help you move forward with clarity, confidence, and code compliance.
We design code-compliant Accessory Dwelling Units (ADUs) customized to your property layout, long-term goals, and budget. Whether you're converting a garage, finishing a basement, or adding a detached structure, our team begins with precise as-built measurements and develops a proposed design that aligns with zoning, building codes, and your vision.
Every ADU we design is thoughtfully integrated with your existing home for safety, function, and long-term value. We also account for factors like setbacks, egress, utilities, and accessibility to help avoid costly delays or redesigns.
With over 18 years of experience serving Massachusetts, we understand the local codes, zoning requirements, and permitting expectations that shape every successful ADU project. From lot setbacks to height limits and utility connections, we anticipate challenges early and design strategically to meet both code and client goals.
At VIACAD, LLC, you get more than drawings. You get honest, professional guidance and a team that prioritizes safety, efficiency, and compliance at every stage. We deliver clear, buildable plans that support fast reviews and smoother approvals. No confusion. No delays. Just smart design that moves your project forward.
An Accessory Dwelling Unit (ADU) is one of the smartest ways to increase property value, generate rental income, and support multigenerational living, all without buying new land. Whether you're planning a detached unit, basement conversion, or garage apartment, the process can be complex without the right guidance.
At VIACAD, LLC, we walk you through every step, from the initial consultation and zoning analysis to final code-compliant plans. We help you avoid common pitfalls like missed setbacks, code violations, and costly redesigns. Our goal is to bring clarity, speed, and professionalism to your ADU project so you can unlock your property's full potential with confidence.
There are six types of Accessory Dwelling Units (ADUs) allowed in Massachusetts, each offering unique benefits depending on your lot, home layout, and long-term goals. Whether you're building a new structure or converting existing space, understanding the available options is key to making the right decision for your property.
Use the diagram below to explore what’s possible and see which ADU type best fits your needs.
Detached Unit: A standalone structure separate from the main house, often located in the backyard. Offers maximum privacy and strong rental income potential.
Attached Unit: Physically connected to the main home, usually added to the side or rear. Shares at least one wall but has a private entrance and separate utilities.
Upper Level Unit: An ADU located on the second floor of an existing home or structure. Often created by converting unused attic space or adding a second-story addition. Ideal for maximizing vertical space.
Garage Conversion: An existing garage, either attached or detached, is converted into a livable unit. A smart way to repurpose space without expanding the home's footprint.
Above Garage Unit: A new unit built above an existing garage. Maintains yard space while adding usable square footage. Requires proper structural support and access.
Lower Level Unit: An ADU built within the basement of the primary residence. Typically the most cost-effective option, offering privacy and ease of access while staying within the home's original structure.
Our initial consultation fee is $400. This fee will be credited towards your full project invoice should you choose to move forward with us!
Currently accepting projects in Massachusetts.
