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Maximizing Your Lot With Attached Family Homes

Read how attached family homes are a cost-effective housing solution that allows you to utilize your space to rent out for extra income or house family members.

November 28, 2019

With housing prices rising faster than ever before, you really need to take advantage of what you have now. Obviously, this is easier said than done if you have a small lot and seemingly not much to work with. But there could be more on your lot than meets the eye! In fact, you could invest in an attached family home to make better use of your space and solve your housing dilemma.

What Is an ADU and Why Should You Build One?

For starters, you should know that an attached family home is considered an “accessory dwelling unit” or an ADU. An ADU is a secondary housing unit located on a single-family residential lot. There are several different types of ADUs that range from basement units to attached units to detached units separate from the main house.

No matter which type of ADU you choose to build on your property, you can benefit from this investment in several different ways. For starters, you can increase the value of your property that will come in handy when you put your house on the market. This is especially true in today’s hot seller’s market.

Secondly, you can potentially rent out the ADU for an additional source of income, no matter if you choose to rent it out long-term to an individual or rent it out short-term on platforms like AirBnb and VRBO in cities and counties where short-term rentals are permitted for your new unit.

Lastly, you can save an incredible amount of money on housing expenses by constructing an ADU for family members to reside in. Adult children and elderly parents typically live in ADUs as a living solution that’s far more affordable than getting their own place or residing in an assisted living facility that can easily cost a few thousand dollars a month.

As you can see, ADUs are a practical and flexible housing solution that can provide a whole host of benefits to the homeowners and the larger family unit.

Can You Even Build an ADU on Your Property?

Before you begin the process of building an ADU on your property, you need to learn more about the qualifications and restrictions in your specific area. California is by far the most popular state for ADUs as a result of sky-high housing prices—with more than 16,000 permits being issued across the state in the year 2019 for a year-over-year increase of 10,000. This increase is largely the result of officials taking action to make building these units easier than ever before.

That being said, it’s important to note that there are still some considerations to keep in mind when building an ADU in California. So here’s what you need to know before you move forward with the ADU permitting, designing, and building processes.

ADUs in California

The California Statewide Exemption ADU regulation sets the maximum size of ADUs at 800 square feet with a maximum height of 16 feet. However, cities and municipalities have been able to increase these limits to pave the way for larger ADUs. Take San Jose, for instance, which allows detached ADUs of up to 1,000 square feet on lots that are less than 9,000 square feet and ADUs of up to 1,200 square feet on lots that are over 9,000 square feet. If you want to learn more about the specifications for your area, be sure to check with the proper authorities or reach out to the design, permitting, and building experts at Cottage for professional insight.

ADUs in California are required to have at least a four feet side and rear yard setback from the end of the unit and the property line boundary. If you are choosing to go with a detached ADU, then the structure may need to be between six to ten feet away from the existing home, depending on local regulations.

ADUs in the state of California must meet health and safety regulations in order to be deemed safe for occupancy. They also must be approved and permitted by the local municipality prior to beginning construction. While this process may seem like a headache, permits are made easy when you work with an experienced stick-built ADU builder providing an end-to-end solution like Cottage.

Why Choose an Attached Unit Over a Detached Unit?

While there are several different types of ADUs to choose from, the two main categories consist of attached units and detached units. Attached units are attached to the existing home structure, whereas detached units are totally separate and often need to be constructed at a certain distance away from the main home. Here are some reasons why you may want to choose to build an attached unit over a detached unit:

  • If you already have an existing structure on the property that can be easily converted into an ADU, it may make more sense to pursue this instead of building an entirely separate structure. Some examples of attached structures that can be converted into ADUs include basements and garages, often for less money than a new detached structure.
  • Speaking of money, this is a huge reason why you may want to choose an attached unit over a detached unit. Instead of building a whole new structure, you’re simply converting an existing one into a living space by adding areas like a kitchen, bathroom, and bedroom. While costs vary, you can expect to spend between $50,000 to $150,000 on an attached ADU conversion. Conversely, prices for detached ADUs often start at $100,000 and can go all the way up to $400,000 or more depending on size, features, and finishes you choose.
  • An attached unit can be more accessible to the main home. As a result, you may not need to add a complete kitchen within the separate unit—you could install a kitchenette with a two-burner stove for necessities only. While this option may not be as lucrative for renting or investing, it is ideal for housing family members that would still maintain some level of access to the main home. This type of ADU provides them with privacy while still being connected to the rest of the family in the home.

How to Maximize Your Lot With an Attached Family Home?

Constructing an attached ADU on your family home is no easy feat. While it’s possible to achieve great results and maximize your investment, it’s definitely not guaranteed. The best thing you can do to maximize your lot with an attached family home is to work with an experienced and reputable ADU builder in your area. If you’re in California, Cottage is a fully custom, site-built ADU company that helps guide you through the entire process from eligibility to permits to design and finally, construction.

We have designed and completed a wide variety of ADUs in different areas of California that range in size from a few hundred square feet to over 1,000. These units can include multiple bedrooms, full-size kitchens, luxurious bathrooms, living spaces, and even laundry units. These units are also fully customizable to meet your needs. For instance, we have constructed accessible units that are safe and ideal for aging parents.

So no matter what your dreams, desires, or restrictions, Cottage can help you design and construct the ideal ADU for your family and property.

Up to Speed on Attached Family Homes

You can easily maximize your lot with an attached family home by using an experienced ADU builder like Cottage that is familiar with local restrictions and regulations. So before you spend more money on a detached ADU, consider converting an area of your home into an attached unit to save you time and money in the process.


Housing Market Reaches Record-High Home Price and Gains in March | National Association of Realtors

Financial Planning: COVID-19 Recession Forces Grown Kids to Move Home | USA Today

ADU Handbook | California Department of Housing