Add space, value, and flexibility to your Framingham home with a custom ADU. Whether you need a backyard cottage, garage conversion, or basement apartment, Millhawlk handles design, permitting, and construction all in one place.
Looking for flexible housing solutions? An Accessory Dwelling Unit (ADU), whether a backyard cottage, garage conversion, or in-law suite, is one of the smartest ways to maximize your homes function and value. Use it for family, rental income, or a private retreat.
We are a full-service ADU contractor. That means Millhawlk handles everything from the custom design and permitting to final construction of your new ADU. We deliver stylish, functional, code-compliant spaces that enhance your lifestyle and investment.
Unsure about permits, costs, or design? Our team of ADU contractors will simplify the process for you, with expert guidance and transparent communication every step of the way.
Every home is different and so is every ADU. Whether you’re converting existing space or building new from the ground up, we have the expertise to bring your vision to life. Below are the most common ADU types we design and build for Massachusetts homeowners.

A standalone structure in your yard—perfect for maximizing privacy. Ideal for rental income, guest suites, or a quiet home office. These custom cottages are designed to complement your property while creating a distinct living space.

One of the most cost-effective ADU options. We transform existing garages into comfortable, code-compliant living spaces with proper insulation, plumbing, and finishes. Great for rentals or multi-generational living without changing your home’s footprint.

Turn underutilized space into income. Basement ADUs require careful attention to ceiling height, egress windows, and moisture control. Our team handles the structural and waterproofing challenges to create bright, safe, legal living spaces.

Expand your existing home with a connected living unit. Attached ADUs share a wall with the main house but maintain separate entrances and utilities—ideal for in-law suites or older children while preserving independence.

Perfect for rural properties with existing structures. We transform barns, outbuildings, and even large sheds into stunning, habitable dwellings while preserving their character and charm. A creative way to repurpose space you already own.
An ADU is more than just extra space. It’s an investment in your home’s value, your family’s future, and your financial flexibility. Here’s why Framingham homeowners are choosing to build with a local ADU contractor.
Offset your mortgage or fund retirement with steady monthly cash flow. ADUs typically rent for $1,500 to $2,800+ per month in Greater Boston, depending on size and location. Short-term rentals through Airbnb or VRBO can generate even higher returns.
Create space for aging parents to maintain independence while staying close. Or provide affordable housing for adult children saving for their first home. ADUs keep family together while respecting everyone's privacy.
Real estate experts estimate a well-built ADU can increase your home's value by 20 to 30 percent. Appraisers recognize the income potential and square footage, making your property more attractive to future buyers.
Today's home office, tomorrow's guest suite. ADUs adapt to your changing needs. Use it as a gym, art studio, hobby space, or private retreat. When life changes, your space can change with it.
Rent long-term for reliable income or use short-term rentals when you need extra cash. An ADU gives you options traditional home additions simply don't offer.
Building an Accessory Dwelling Unit should be exciting, not overwhelming. Our streamlined process handles the complexity, so you can focus on the possibilities.
We start by understanding your goals, rental income, multi-generational living, or home office? Our architects create custom ADU plans that maximize every square foot while reflecting your style.
Massachusetts zoning laws vary by town. We handle all permit applications, zoning analyses, and approvals so your project is 100% compliant before we break ground.
With plans approved, our builders get to work. We manage every trade, inspect daily, and keep you updated so your ADU is built on time and on budget.
We don’t leave until you’re thrilled. After a detailed walkthrough, your new ADU is ready, whether as a rental, guest suite, or private retreat.
Planning an ADU, whether a backyard cottage, garage conversion, or basement apartment, comes with lots of questions. We answer the most common ones about Massachusetts zoning laws, construction timelines, costs, and rental potential. If you don’t see your question here, our team is here to help.
An Accessory Dwelling Unit (ADU) is a secondary living space on the same property as a single-family home. It has its own kitchen, bathroom, and entrance—think backyard cottage, garage conversion, or basement apartment. In Massachusetts, ADUs are often allowed under state law to help ease housing shortages.
Yes, in most Massachusetts towns, you can rent out your ADU. Many homeowners use them for long-term rental income, while others list them as short-term rentals (like Airbnb). However, local ordinances vary, so we recommend checking town-specific bylaws. We can help guide you through what’s allowed in your area.
A well-built ADU can significantly increase your home’s resale value. Appraisers and real estate experts often cite a value increase of 20% to 30%, depending on the unit’s size, quality, and rental income potential. It’s one of the smartest investments you can make in your property.
Yes. Garage conversions are a popular ADU option in Framingham. Converting an existing garage into a living space often requires structural modifications, new electrical and plumbing, insulation, and proper egress. A qualified ADU contractor can assess your garage and determine what’s needed to create a code-compliant, comfortable living space.
Yes, ADUs require permits just like any new construction or major renovation. This includes building permits, and often zoning approvals. The good news? Recent Massachusetts laws have relaxed zoning restrictions in many communities to make ADUs easier to approve. We handle the permit applications for you.
ADU costs in Massachusetts vary widely based on type and size:
We provide free, detailed quotes tailored to your specific project and property.
No, they are different. An auxiliary building like a shed or garage is for storage or vehicles, not for living. An ADU is a habitable dwelling with sleeping areas, a kitchen, and a full bathroom. It’s designed as independent living quarters for a tenant or family member.
Framingham allows several types of ADUs, including detached backyard cottages, attached additions, garage conversions, and basement units. Each type has specific zoning requirements related to size, height, setbacks, and parking. A knowledgeable ADU contractor can help you determine which option best fits your property and needs.
Yes. Real estate experts estimate a well-built ADU can increase your home’s value by 20 to 30 percent. Beyond appreciation, ADUs generate rental income, provide flexible living space for family, and offer long-term financial flexibility. With Framingham’s strong housing market, an ADU is one of the smartest investments a homeowner can make.
Millhawlk is a full-service ADU contractor in Framingham with in-house architects, engineers, and builders. We handle every aspect of your ADU project from design and permitting to construction and finishing. Our integrated team eliminates finger-pointing, streamlines communication, and ensures your project is completed on time and on budget. We know Framingham’s zoning and building codes inside and out so you don’t have to.
ADU construction costs vary based on size, type, location, and finishes. In the Greater Boston area, detached ADUs typically range from $150,000 to $400,000+, while garage conversions and basement units are often more affordable. The best way to get an accurate estimate is to schedule a consultation with a local ADU contractor who understands Framingham’s specific building requirements and can provide a custom quote based on your property and goals.
Unlock your property’s potential with a custom Accessory Dwelling Unit. As a full-service ADU contractor in Framingham, we handle everything from design and permitting to construction.
Considering an ADU but have questions about cost, permits, or design? You’re not alone. ADUs are a smart way to add space, value, and flexibility, but the process involves important decisions.
Let Millhawlk Design & Construction guide you. From initial consultation to final inspection, we’re with you every step of the way.