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Our experienced team drafts a detailed estimate, which we then finalize together to align with your vision and budget
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When existing space in your primary dwelling is not enough for comfortable living, the question of how to extend your main home without much expense arises. Some might consider buying or renting another house or apartment. However, the most affordable option would be to build an attached accessory dwelling unit, or attached ADU, on your lot. This is a perfect choice for those who want to make their living space bigger without changing anything in the existing home.

Being one of the affordable housing options, attached ADUs have plenty of other benefits as well. Homeowners who have aging family members can easily accommodate their loved ones nearby so that any necessary help can always be provided. The attached units are also suitable for those who have adult children living with them, as such types of ADUs provide more privacy in the living space. No matter what you are planning to get secondary dwelling units for, you can always design them for your needs and make more use of existing space on your property.

Want to know more about attached ADU? Read further to learn more about the benefits of attached accessory dwelling units, their specificities, and ADU construction services provided by ADU Builders Bay Area. Many homeowners have already made their life better by adding an attached unit to their primary home, and you can become one of such lucky people too!

Attached ADU and Detached ADU Types 

An attached accessory dwelling unit is one that is connected by a common wall with your primary residence and usually has its own entrance from the outside. However, attached ADUs differ from detached ones by the fact that they also provide an entrance from the primary dwelling, which makes it more comfortable for some homeowners.

Detached ADU, on the other hand, is a separate housing unit that has its own separate connections for utility. Such ADUs are also located on the same lot, but they only provide separate entrances to the residents. A backyard cottage of this type is usually placed a couple of feet away from the main house.

Attached ADUs differ from the detached ADUs in the following ways:

  • According to the ADU ordinance, the square footage of attached accessory dwelling units must be no more than half of the square footage of the main house. The maximum size for an attached ADU can also vary widely depending on local regulations. Detached ADUs do not have such a requirement, meaning they can have even more square feet than the existing home.
  • Although attached ADUs are limited in the size of the structure, they become a more affordable option than detached ADUs when it comes to property taxes that must be paid for all types of ADUs. Also, the construction costs for an attached unit are much lower, which might be great for low-income families.
  • Unlike detached ADUs, for the attached ones, you do not need to provide any parking space. It allows you to save more precious space on your property for some other needs, like a garden, a playground, or a spacious backyard.
  • Also, the property value for an attached “granny flat” might be even higher, despite the smaller size. Many people, when exploring the housing market, prefer accessory dwelling units with not only separate entrance options but ones maintaining the connection with the main structures as well.

No matter what your needs and preferences for attached ADU are, ADU Builders Bay Area is ready to take on your construction project. Our reputable builder company has years of experience in constructing ADUs, and we use modern solutions throughout the whole process. With ADU Builders Bay Area, you can be sure that you will get the accessory dwelling unit that you wanted in the end.

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Attached ADU Advantages 

Having an ADU constructed on your property comes with many benefits for all homeowners. If you are afraid that the cost of construction is not worth it, you should not be. These accessory structures can provide you not only with more comfortable living space but also with potential rental income and advantages over other homeowners on the housing market.

Still not sure whether building an attached ADU, would be a good investment? Consider the following rewards that you can get from having either an attached or detached ADU constructed on your property:

  • Housing family members and friends. Whether you have a lot of guests coming over frequently or you need a granny flat for your elderly relatives to live in, an ADU structure is a perfect housing option for this. With an accessory dwelling unit, you do not have to worry about finding enough space in the primary residence to accommodate everyone.
  • Getting more personal space. Nowadays, a lot of people work from home, and new construction for a personal office might be a necessity. Having an attached or detached ADU allows you to separate your working zone from other personal areas, like a bedroom or a living room, which can help you to improve your work-life balance. What is more, you can dedicate the accessory housing to your interests and create a studio or a workshop there.
  • Receiving rental income. Even if there is enough space in your primary residence, having an ADU might be beneficial in terms of rental income. Even low-income homeowners can expect the cost of construction to pay off if they find someone willing to rent the accessory property. This financial source can also be useful for paying out your property taxes.
  • Saving on the cost of construction and maintenance. Both attached and detached ADU housing has a smaller construction cost compared to building a brand-new home or even renovating the existing primary residence. Compared to the detached ADU, the attached one is even more affordable as it is based on the existing foundation and connected to the main house.
  • Increasing property value. A granny flat on your property can make a big difference in the property value, which is especially important if you are planning to sell the house in the future. To maintain as much potential profit as possible, analyze what kind of property with an ADU is the most demanded in your area.

Plenty of benefits are awaiting those who decide to build an attached ADU. To make sure that everything is done in the right way and you get to receive more advantages from your ADU, it is better to hire professionals who know exactly what they are doing. Our specialists at ADU Builders Bay Area are ready to guide you through the whole process of ADU planning, building, and design.


Attached ADU Variety 

When it comes to ADUs, there are many different types that homeowners can construct on their property. Your ADU does not necessarily have to be a new construction, as it can also be converted from an existing garage or other unused parts of your home, like a basement. Moreover, if your property has some specific features, a custom plan for an ADU can be created so that everything complies with the local laws and other provisions.

Here are some of the most common attached ADU types that one can add to their property:

  • Junior ADUs 

This is a new construction that is connected with the existing home, and its main distinction from other types is in its size. Usually, a junior ADU is no bigger than one room, and it is built to add some service areas, like a laundry room, to the main structure.

  • Garage conversion ADUs

If you have an existing garage on your property and it just stands there with no use, consider making a garage conversion to make those precious square feet count. A garage conversion can also be done for detached ADUs, but the cost of them is generally higher.

  • Interior ADU structures 

Interior ADUs are great for those who have additional unused space in their homes. Usually, such a structure is done in the basement or the attic. The creation of this ADU includes not only the renovation of the space but also the addition of some elements, like doors, windows, and utility systems.

Property owners with some extra space on their lots should definitely consider getting an ADU. While such a structure can help to increase the comfort of living majorly, it also allows you to get some additional income and change the property value for the better. To get the best ADU building services, contact ADU Builders Bay Area and start planning a new property structure right now.

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At ADU Builders Bay Area, we bring your construction visions to life. Our expertise lies in crafting ADUs, complete home renovations, and initiating new builds for both residential and commercial spaces. Our dedicated team prioritizes swift, accurate solutions customized to your requirements.

Our commitment to dependable craftsmanship, professionalism, and meticulous attention to detail is highly valued by our clients. Leveraging our deep industry experience, we efficiently address and resolve potential obstacles for seamless project completion. Proudly displaying our certifications and recognitions, we eagerly await the opportunity to collaborate with you on your next project.


Frequently Asked Questions — FAQ

What does ADU stand for?

ADU stands for an accessory dwelling unit, which is an additional building placed on the same lot as your primary housing. ADUs can be of different types, including detached, attached, and junior ones. While some ADUs are built from scratch, others are simply converted from already existing structures. For instance, homeowners can do a garage conversion or basement renovation to create a more practical space, like a granny flat, from something that has been out of use.

What does an attached ADU mean?

An attached ADU means that the structure of the accessory unit is connected in some ways with your main housing. Usually, these two units share a common wall and sometimes even an entrance. An attached ADU can have a separate entrance as well. If it is more convenient for the homeowners, the utility systems of the main home and the secondary unit can be connected as well. An attached ADU might also be in the form of an interior ADU, in which case some already existing part of the home is turned into a new living space.

What is the difference between attached and detached ADU?

The main difference between attached and detached accessory dwelling units is in their connection with the primary housing. The first type has common sides with the main home, as well as common entrances and utilities. The second type usually stands separately from the primary dwelling, has its separate entrance, and can be much bigger in size than the attached unit. Both kinds of ADUs can be built anew or converted from something like a garage.

What are the advantages of an ADU?

Building an ADU on your lot can bring a lot of benefits. First of all, you get to increase the property value, which is always important for your position in the housing market. Second of all, you can create a new living area for your elderly parents, grown-up kids, or frequent visitors. What is more, an ADU can become an additional source of money, and you can easily increase their budget this way. Last but not least, you can turn an ADU into anything you like, whether it is a home office, personal studio, home cinema, gym, or playing area for kids.

What are the disadvantages of an ADU?

One of the ADU's limitations is that with increased property value, your taxes also get bigger. What is more, planning an ADU can be a tiring process, as you have to get permits for your architectural plans from the officials. In order to avoid the whole paperwork and repeating attempts to draw the plan correctly, it is better to hire a professional team of ADU builders who are ready to help you from the very first to the finishing steps of creating an ADU.
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