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Attached Homes Provide Flexibility to Families

Attached family homes provide a unique solution well-suited for many different family structures. Learn how to build one for your family here.

December 1, 2020

Coming up with a housing solution that meets your family’s unique needs can be a challenge. You have many options to choose from: tiny homes, mobile homes, or ADUs. Luckily, attached family homes provide the perfect balance of separation and connectivity that can work well for many different family structures.

Here’s what you need to know about these units and how you can design the perfect version for your family:

What Is an Attached Family Home?

An attached family home is a separate unit that’s built onto an existing home structure with at least one shared wall. Also known as attached accessory dwelling units or ADUs, attached family homes often come with their own bedroom, bathroom, kitchen, and living areas.

As a result, attached family homes can act as fully-functional units that don’t require any access to the existing home. Or, they can also be designed and built to be more connected to the existing home, depending on your space, budget, and needs.

Why Build an Attached Family Home?

Attached family homes provide a unique housing solution that’s ideal for many different types of families.

Here are just a few reasons why you may want to consider building one of these units onto your home:

Supporting Your Loved Ones

  • Keep aging parents close to home: Many families struggle with caring for aging parents. Attached family homes provide a great solution that’s often better than moving them into the main house or into an assisted living facility.

With an attached family home, you can keep aging parents close to home and make care easy while still providing them with their own space and independence. This will make what can be a difficult transition easier for everyone involved.

  • Help adult children starting out: Young adults these days are facing a lot of challenges. Housing prices and rents are high while wages remain stagnant. Additionally, young adults are often burdened with student loans from college. This can make it very difficult for them to afford to live on their own.

Attached family homes can help young adults save money while still having a place of their own. They can then use the money they save to pay off their student loans or make a down payment on a home.

  • Be a better host: Even if you don’t have aging parents or adult children that need a place to live, building an attached family home helps you be a better host when you do have guests come into town.

Rather than booking a hotel room, you can spend more time with your guests since they’re right next door. At the same time, they have enough privacy so that they feel comfortable.

Financial Reasons

  • Work at home permanently: Transitioning to work from home can be challenging. Working in the main house often comes with tons of distractions that can negatively impact your productivity. However, you can build your own dedicated office space with a separate attached unit that comes with everything you need, including a bathroom, mini-fridge, kitchen space, and more.
  • Earn extra income: It’s never a bad thing to have an additional source of income. Attached family homes can provide just that when you rent them out on either a long-term or short-term basis.

Just make sure to check local regulations when renting out these as some areas may prohibit certain types of rentals and may require features like dedicated parking spaces if you’re not near public transportation.

  • Increase home value: It’s also never a bad thing to increase your home value, and attached family homes can add a ton of value to your property that will come in handy when you decide to sell. For the reasons stated above, attached family homes are in high demand; buyers are willing to pay a premium for properties that already have functioning units.

How Do You Build an Attached Family Home?

Building an attached family home is easy with companies like Cottage. Cottage is a custom ADU builder that offers a simple and hassle-free process by handling everything from permitting to construction.

Here’s how the process works:

  • Feasibility: Cottage will discuss your property’s details for free with you and schedule a site visit if it’s a good fit to determine what type of ADU is best suited for your property, goals, and budget. Cottage will determine the best location for your ADU and figure out how to incorporate any additional utilities, foundation, local regulations, etc.
  • Design: Cottage will then help you design your perfect space along with designers that are well-versed in working with ADUs. During this phase, you will develop a functional floor plan for your family and select beautiful finishes. It’s easy to visualize your future attached family home thanks to 3D plans drafted by your designers.
  • Permitting: Cottage then works to streamline the permitting process with local authorities thanks to full architectural sets. What can often be a frustrating process is made easy thanks to live updates in your online portal and constant communication with your dedicated representative.
  • Construction: Cottage matches you with an experienced ADU builder in our ADU contractor network that’s been fully vetted, licensed, and insured. All of Cottage’s projects come with a 30-day no-questions-asked callback period and a one-year workmanship warranty to give you full confidence in the process.
  • Move-in: Once construction has been completed, you’re all set to move into your new attached family home and start enjoying it.

How Much Does It Cost To Build an Attached Family Home?

Building an attached family home can save you a lot of money, especially with the current housing and rental markets that are at all-time highs.

But exactly how much does it cost and how much money can you save?

The cost of your project is determined by the size of your addition, your chosen finishes, and the provisions of your existing home. Generally speaking, costs can range between $200,000 to over $300,000. However, when you choose an all-inclusive builder like Cottage, you can expect to see a transparent estimate for your entire project since you’re using in-house architects, designers, and in-network contractors under one company.

While $300,000 might seem like a lot, let’s compare that number to current housing prices in California. In Los Angeles County, the median sold home price is $795,000. In San Jose and San Francisco, that number is even higher.

Home prices are high, and rents aren’t much better. In Los Angeles, the average rent price for an apartment is over $2,000 and is expected to rise to $2,325 by 2023. And in San Francisco, the average rent price is over $3,000 at $3,244 for an average apartment size of just 740 square feet.

With these numbers, you’ll spend over $30,000 a year on rent alone. And with renting, all this money goes down the drain instead of building home equity. This is why so many families are turning to attached family homes, as you’re able to save money, build equity, and increase property value all at the same time.

What Are the Alternatives to Attached Family Homes?

If you’re still not sure if an attached home is the right solution for your family, here are some alternatives to consider:

Conversion Units

Conversion units take existing space within your home and convert it into a separate and functional unit. Conversion units are typically made from garages and basements.

Depending on the space you’re working with, you may be able to transform these spaces into a separate unit with its own bedroom, bathroom, and kitchen area. If you’re working with a smaller space, you can embrace the “studio” approach by including an efficiency kitchen and a smaller bathroom.

Detached Units

Detached units are completely separate from the main home and allow for maximum privacy. The process of building a detached unit looks a lot similar to building a home from scratch since you have to incorporate a separate foundation and new utility connections.

And while this may seem like a complicated and time-consuming process, building a detached unit from scratch can be more straightforward than building an attached unit onto an existing home.

For example, when you build an attached unit, you may need to meet certain safety standards that involve placing fire-rated separations between the existing home and the new unit. This step can impact both the timeframe and the cost of your project.

On the other hand, when you build a detached unit, you often have to meet certain local regulations involving minimum lot setbacks. For example, if you’re in Los Angeles County, your detached unit must be at least four feet from the side and rear lot lines as well as at least six feet from any existing structures.

Setback regulations are more complicated in San Jose, where your detached unit must be set back at least 45 feet from the front property line. Additionally, rear and side setbacks less than three feet from the property line may be subject to fire mitigation measures.

Final Thoughts

No matter what your family needs, Cottage can help you design the perfect solution in an attached family home. Reach out to the experts at Cottage today for a complimentary consultation and estimate.


Student Debt Can Make Buying a Home Feel Impossible | CNBC

17 Items You Need to Set up an Efficient Home Office | The Balance Small Business

Accessory Dwelling Unit (ADU) | Los Angeles County Department of Regional Planning

What L.A. County’s median home price — $795,000 — buys in six areas | LA Times

USC report: Renting an apartment in Southern California is about to get a lot more expensive - ABC7 Los Angeles