Accessory Dwelling Units, or ADUs, are becoming a smart way for homeowners to add value, create extra living space, or earn rental income. Starting an ADU project takes planning, patience, and the right steps to make sure the process runs smoothly.
Starting an ADU begins with checking local rules, setting a budget, choosing a design, hiring an experienced builder, getting permits, and planning utilities. Proper planning ensures a smooth build and long-term value for your property.
With my background in land analysis, home building, and home remodeling, I’ve guided many families through this journey. This guide walks through each step so you know how to start your ADU the right way.
Adding an ADU brings several benefits. Some homeowners build one to create a private space for parents or adult children. Others see it as a way to generate rental income. Many simply want to add long-term value to their property. An ADU can be a detached unit in the backyard, a garage conversion, or even a basement apartment. No matter the style, the end result can provide comfort and financial stability.
Every city and county has its own zoning codes and building requirements. Some allow ADUs in all residential zones, while others limit them to certain lot sizes. Height limits, parking rules, and design standards also come into play.
Getting this information early avoids delays and costly redesigns.
An ADU is a major investment, so having a clear budget is vital. Costs vary based on size, type, and finishes. Detached units often cost more than garage conversions, but they also provide more privacy.
Working with a builder who has experience in ADUs helps you get an accurate estimate.
Designing an ADU is about balancing comfort, function, and style. Even small spaces need to feel open and livable.
A good design respects the main home while giving the ADU its own character.
Building an ADU involves architects, engineers, contractors, and city inspectors. Trying to manage it all alone can be stressful. A builder with a full-service approach can handle coordination, saving you time and stress.
Choosing the right partner makes a big difference in both the process and the outcome.
Permits may feel like a hurdle, but they protect you from future legal or safety issues. Submitting detailed plans upfront helps avoid rejections. Most cities require:
Once permits are approved, construction can begin.
The construction phase is where your plans turn into reality. Depending on the design, this may involve:
Regular site visits and progress meetings keep things on track.
An ADU needs water, sewer, power, and often gas. Extending these systems from the main house or creating new connections takes careful planning. Some cities require separate utility meters for rentals, while others allow shared service. Discuss these options with both your builder and the utility providers before construction starts.
An ADU should serve your needs for years, not just in the short term. Consider how it might be used over time.
Building with flexibility helps your ADU adapt as life changes.
After construction ends, the final touches make the ADU feel like home. Small details like durable flooring, easy-to-clean countertops, and energy-efficient appliances create a comfortable and practical space. Landscaping around the unit also improves curb appeal and blends it into the property.
Once the final inspection is complete, the ADU is ready to use. Some owners move in family members right away. Others begin the process of renting it out. Make sure to check short-term rental rules if you plan to use platforms like Airbnb, as many cities restrict them.
Many homeowners start ADU projects without fully understanding the challenges involved. Avoiding these mistakes can save time, money, and stress.
Some homeowners dive into construction without checking local zoning laws, building codes, or HOA rules. Every city has different regulations for ADUs, including limits on size, height, and distance from property lines. Failing to review these rules can result in rejected plans, fines, or costly redesigns. Even small oversights, like parking requirements or utility connection rules, can delay the project significantly. Always gather all relevant information from your city planning office before beginning any work.
ADUs involve more than just construction costs. Many homeowners focus only on materials and labor but forget soft costs such as permits, design fees, or utility extensions. Unexpected site conditions, like poor soil or drainage issues, can increase expenses. It is important to include at least 10 percent extra in your budget for contingencies. Underestimating costs often forces homeowners to cut corners, which can affect quality or delay the project.
Choosing a builder or contractor without ADU experience is a common mistake. ADUs require specialized knowledge, from compact layouts to city inspection procedures. A builder unfamiliar with ADU requirements may make errors that result in rework or safety issues. Take time to review references, inspect past projects, and ensure the team communicates clearly. A reliable team keeps the project on schedule and ensures the unit meets both your needs and city requirements.
Some homeowners focus only on short-term goals, such as immediate rental income or guest space. They neglect future needs, which can reduce the unit’s usefulness over time. Consider how the ADU might serve different purposes in the future. Planning for flexibility ensures the space remains valuable for years.
An ADU requires ongoing maintenance just like the main home. Ignoring tasks like roof upkeep, plumbing checks, and exterior cleaning can reduce the lifespan of the unit. Planning for maintenance during design and construction saves effort later.
Starting an ADU project can feel like a big step, but with the right preparation it becomes manageable. From learning the rules and setting a budget to designing the space and hiring the right team, every step matters. Homeowners who take the time to plan carefully see their investment pay off in comfort, flexibility, and long-term value.
As the owner of Giudice Builds, I’ve seen firsthand how an ADU can transform a property. Whether it’s creating a rental unit, giving family members a private home, or boosting property value, the process is worth the effort. If you’re ready to begin, take the first step with research and planning. From there, each step builds toward a space that improves your home and lifestyle.
Giudice Builds was one of the best experiences I had in having something built in my home.