Top Remodeling & Design


Which Is Better: An Accessory Dwelling Unit (Adu) Or An Addition?


One of the most common questions that homeowners ask themselves is whether or not they should build an accessory dwelling unit (ADU) or if they should add on. As it turns out, there are many benefits to building both types of homes. Which option will be best for you?

Do you have a large family and not enough bedrooms? Do you need more space for your home office or to house guests? Maybe it’s time to consider an addition. Which is the better choice: building an Accessory Dwelling Unit (ADU) or adding onto your existing structure? 

Accessory Dwelling Unit (ADU), also known as a Granny Flat, is typically located on the same property but separate from the main dwelling. It can be attached or detached and may share common walls with other structures like garages and sheds. This type of living arrangement allows homeowners additional room without having to move out and buy another piece of land — plus there are tax breaks! The laws regarding ADUs vary by state so check before proceeding with this project.

  • Affordable way to provide more space for your family
  • Provide a lower cost alternative when buying property 
  • Save time and expense of moving out and into new houses
  • Customize the design to suit your needs


In addition, on the other hand, is a separate structure that’s built onto an existing one. It requires its foundation and often has to meet building codes for both areas. While it can be attached with siding or drywall, zoning laws may still require you to build two structures instead of merging them into one larger home. That said there are opportunities for commercial properties as well which might make this option more attractive than adding a second floor above ground level. Which do you think would work better in your case? Which type of project will provide more benefits overall?

  • Easier option for those who have limited time/resources/energy
  • Renovating without the hassle of zoning laws and permits
  • Stay within your property boundaries but still add significant square footage to your home


Do you find ADU homes appealing, but are unsure whether or not to construct an addition? Let’s go through the advantages and disadvantages of both accessory dwellings and add-ons.


What Is An ADU?

ADUs are accessory dwelling units. These small, separate houses often come with their lot and can either stand completely separate from your single-family home or be attached to it for more private living space that doesn’t have the same yard requirements as a typical main house on one property.

A tiny house in the backyard, a basement apartment, or an apartment over your garage are all examples that could be used to create ADUs. 

ADUs can be a great way for homeowners on tight budgets to expand their living space and enjoy more independence.  They are legally considered to be a part of the main property as an attached or detached single-family dwelling. This means that they cannot be sold or bought separately from your main house.


The Pros And Cons Of Accessory Dwelling Unit (ADU)

The number one reason people build ADUs is to house a family member or make some extra income renting them out.


Pros Of Accessory Dwelling Unit (ADU)

There are many benefits to adding an ADU to your property. The return on investment can be very favorable when you consider how much it costs to build an ADU versus the potential increase in property value.

ADUs are a great solution for those who want to have friends or family visit, yet not feel crowded in their own home. With an ADU you can host guests of all sorts while still maintaining privacy and having your space too.

There are many reasons to build an ADU on your property, but one of the most common is for extra rental income. Whether you furnish it and rent out short-term or offer it as longer-term rentals, doing so can significantly cut down mortgage payments in exchange for renting out a room through Airbnb.

  • You can use your ADU as a guest house
  • Keeps guests close and offers privacy for both parties
  • It’s perfect for those who want to be able to entertain without feeling cramped  
  • Offers more living space in an already existing home
  • Earn extra income by building an ADU
  • Save on mortgage payments by renting it out for short-term rentals
  • Stand to make more money than you expected 
  • Rent out your room with Airbnb


Transitioning into independence is difficult, and for those who have children that will soon be leaving the nest, an ADU can provide a great low-cost housing option. This allows them to save money while attending school without compromising on space in your home. 

  • Increase your monthly cash flow
  • Keep the kids close but have some independence
  • Save money on rent in an expensive market
  • Independence with a safety net


If you are looking for a way to take care of your aging parents while still providing them with an independent lifestyle, consider converting one room in the house into an attached dwelling unit.

  • Save on rent for a long-term care facility
  • Lessen the burden of paying to keep two homes maintained
  • Stay close to family while providing your parent or parents with an independent living unit


Detached structures are perfect for people who work from home. You’ll have your own space to focus in and be more productive, it can also serve as a workspace where you do hobbies or act as an art studio.

  • Have a space to work from home that’s detached and private
  • Use your ADU as a workshop or art studio for hobbies
  • Create more space in the city to reduce crowding and traffic 
  • Live close to your workplace


Cons Of Accessory Dwelling Unit (ADU)

There are many different uses for an ADU. So, depending on what you plan to use your custom-designed or prefabricated ones for, the cons can vary greatly.

One of the most important things to consider when taking on an elderly parent as landlord or caretaker is that it could disrupt your daily life. It can be difficult to share your outdoor space with someone else. Landlords will need to maintain a positive relationship and do repairs or maintenance on the property themselves, but there is always the option of hiring an outside company for this work.


The Pros And Cons Of Additions

Some people prefer to add to their homes instead of building an accessory dwelling unit. The benefits and drawbacks of this approach depend on what you’re looking for in your new construction.


Pros Of Additions

When you are ready to add some living space without leaving the neighborhood or having an entirely new home, consider building out an addition. You can have all of your family in one house while still being able to enjoy more room than what they require with less hassle.

Adding onto your home is the perfect way to make it more than just enough. You can get exactly what you need without relying on others, making this an amazing decision for the family.


Cons Of Additions

When you add on to your home, it can be disruptive and costly. Your daily life may change as well which means that this is not always good for the value of what was bought originally.

Construction on the addition is right inside your home, rather than an ADU which can be at quite a distance. Depending on how big of a project it is this means that you may have to live with dust and noise while construction takes place. You could choose to relocate temporarily while the construction is underway but this in itself will disrupt you at home.

Another thing to consider is that adding on may not necessarily be less expensive than relocating. With all of the expenses associated with obtaining permits, inspections, and supplies as well as labor for constructing an addition, it might become quite costly.


Accessory Dwelling Units Are Frequently A Better Alternative To Additions

ADUs are frequently a better option than additions for several reasons. Whether you’re looking to purchase an ADU home or just need space, the product must work well with your specific circumstances and changes over time as needed by family members to make this decision worthwhile.

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