Accessory Apartments: An Assonet Addition
Estimated reading time: 6 minutes
Accessory Apartments are like Additions but with one notable difference, they have a kitchen in them. Additions can have bedrooms, bathrooms, living rooms, etc., but as soon as you add in a kitchen it becomes an Accessory Apartment.
One current project we are working on now is an Accessory Apartment in Assonet, MA.
The client was looking to have the Apartment added on to their house for their family who was moving back with them.
Key Takeaways
- Accessory apartments are self-contained living spaces that include kitchens and are built on the same lot as a primary residence.
- They offer benefits like multigenerational living and generating passive rental income, making them a smart investment.
- Homeowners can choose between attached and detached units, each with its pros and cons for privacy and cost.
- Understanding local zoning laws and permitting is crucial before starting construction on accessory apartments.
- Budgeting realistically and incorporating universal design features enhances functionality and accessibility of the space.
Table of Contents
They were looking for two bedrooms, a full bathroom, a half bathroom, living room, and kitchen.
Originally, they wanted a two-story addition on the side of the main house, but after meeting with the client on-site and discussing some possibilities they said that they were also considering a one-story option and possibly on the back or opposite side of house.
See Also: Can I Build an ADU on My Property
With two height options and three sides of the house to work with, we were able to quickly draw up several Design Options: a one-story off the side, a two-story off the side, and a two-story off the back.
Unlocking Property Potential with Accessory Apartments
Homeowners today are increasingly looking for creative ways to maximize their property’s potential.
If you are considering a major home upgrade, you might be asking: what are accessory apartments?
Simply put, accessory apartments are independent, fully functional living spaces located on the same lot as a primary residence.
Whether you want to enjoy multigenerational housing benefits by keeping aging parents close, or you are looking to generate passive income from rental suites, adding one of these units is a highly strategic investment.
Choosing the Right Structure
Integrating accessory apartments in single family housing opens up several exciting architectural possibilities. When mapping out your project, you will first need to weigh the pros and cons of a home addition vs separate structure.
- Attached Units: Repurposing existing square footage is often the most cost-effective route. Converting garage into living space or finishing a lower level are incredibly popular attached options that utilize your current footprint.
- Detached Units: When comparing detached vs attached dwelling units , a standalone unit offers maximum privacy. Options range from custom-built cottages to placing a tiny house on a permanent foundation in the backyard, giving tenants or family members their own distinct space.
Navigating Legalities and Permits
Before you break ground, it is crucial to understand local municipal land use regulations. Zoning codes dictate exactly what you can and cannot build on your property.
Knowing how to permit a backyard cottage early in the planning phase saves both time and headaches. Check your local granny flat zoning laws to ensure strict compliance with size limits, height restrictions, and property setbacks.
See Also: ADU Homes: Trends and Market Insights
Additionally, if you opt for a subterranean build, strict adherence to basement apartment fire safety requirements—such as installing proper egress windows and fire-rated drywall—is absolutely non-negotiable for the safety of your occupants.
Budgeting and Smart Design Considerations
Understanding the true cost of building an in-law suite is vital for setting a realistic budget. Fortunately, there are numerous secondary suite financing options available, such as home equity lines of credit (HELOCs) or specialized renovation mortgages, to help fund the project. Ultimately, the upfront expense is often offset by the long-term benefit of increasing property value with ADUs (Accessory Dwelling Units).
When you move into the design phase, keep these practical elements in mind:
- Infrastructure: Plan your utility connections for secondary units early. Upgrading electrical panels, extending plumbing from the main house, or adding separate meters requires professional assessment.
- Inclusivity: Consider designing for universal accessibility. Implementing features like zero-step entries, walk-in showers, and wider doorways ensures the space comfortably accommodates everyone, regardless of age or mobility.
The Bottom Line
Building well-planned accessory apartments in single family housing is much more than a standard home improvement project; it is a smart lifestyle and financial choice. By understanding local regulations, exploring diverse financing avenues, and prioritizing accessible design, you can create a beautiful, highly functional addition right in your own backyard.
Q&A – Accessory Apartments
An accessory apartment is an independent, fully functional living space on the same lot as a primary home. Homeowners add them to support multigenerational living—such as keeping aging parents close—or to generate passive rental income. Beyond lifestyle benefits, well-planned ADUs are a strategic investment that can increase overall property value.
Attached units repurpose existing space and are often the most cost-effective option—think converting a garage or finishing a lower level. Detached units, such as a custom backyard cottage or a tiny house on a permanent foundation, offer maximum privacy with a distinct, standalone space. The right choice depends on your budget, desired privacy, and how you want to use your current footprint.
Start by reviewing your local municipal land use regulations, which set what’s allowed on your lot. Check “granny flat” zoning laws for size limits, height restrictions, and setbacks, and learn the steps for permitting a backyard cottage early to avoid delays. For basement apartments, strict fire safety measures—like proper egress windows and fire-rated drywall—are non-negotiable.
First, understand the full cost of building an in-law suite to set a realistic budget. Financing options can include home equity lines of credit (HELOCs) and specialized renovation mortgages. While upfront costs can be significant, many homeowners recoup value through added rental income and by increasing property value with an ADU.
Plan utility connections early—upgrading electrical panels, extending plumbing, and possibly adding separate meters often requires professional input. Prioritize universal accessibility with features like zero-step entries, walk-in showers, and wider doorways so the space works for all ages and mobility levels. Thoughtful infrastructure and inclusive design make the unit safer, more comfortable, and more marketable.
Neil has over 20 years’ experience on a range of large (15,000 sf) and small (500 sf) residential, non-profit, and commercial projects with a small business focus. He has two kids with his wife, Victoria, and loves family time camping, hiking, and traveling. While he grew up in New England, Neil is a diehard Buffalo Bills fan!
