ADU rules

Seattle ADU/DADU Rules

If you read, understand, and follow Seattle's rules for constructing an ADU you will be all set. Take your time and call us if you need guidance on the construction and permitting bits.

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Rules for Your New Backyard Cottage


When you plan to build your background cottage, Seattle ADU rules for the homeowners are essential for the people of Seattle. You have to follow them to build up another private property with the assistance of Seattle ADU builders. You must know the rules. It will help you build up the structure with proper measurement. First, you have to understand what exactly ADU is. Let's see about it in brief. 


DADU Or Detached Accessory Dwelling Unit


Some of us have some extra space where we can build another smaller unit with your main building. A detached accessory dwelling unit or a DADU is a living place with facilities like a bedroom, kitchen, washroom, etc. Valid permission from the authority is required to build them. A DADU unit is built upon this permission. But you may also make them separately from your house but within the boundary area. The name of it is the DADU or detached accessory dwelling unit. ADU is known to people with so many names. Like attic apartments, backyard houses, garden cottages, mother-in-law suites, granny flats, tiny houses, etc. You can address them by any name you prefer. 


Seattle DADU Rules


By now, we have understood what the DADU is. But now, we will discuss the city of Seattle ADU rules. There were some rules earlier. But after time, they have been changed according to the need of the time. So, they introduced the new rules. Thus, the people of Seattle have got some facilities like eliminating the regulatory barriers. Because of that, the landlords will be able to build up the ADU or attached accessory dwelling in their area. 


Required ADU Permits


You will need some permissions from the respective authority to build an ADU. They are:


  • To build up a new house with the older one, you have to take permission from the Alteration Permit or Construction Addition
  • For building a separate unit, you have to take permission from Alteration Permit or Construction Addition
  • For the validation of the previous unit, you have to take permission from the Construction Permit
  • For the new unit, it is necessary to take the electric connections; you have to take permission from the Seattle City Light.


Seattle ADU Rules: Know the Eligibility of Your Property for the ADU


To know the capability of your property for an ADU, you need to consider a few facts. As the law of Seattle is strict, they have specific rules for ADU. Your property must fulfill them to build an ADU further. 


  • The homeowner can leave the area. They don't have to stay there.
  • The minimum size of the area will be 3,200 square feet.
  • The width of the area will be 25 feet. 
  • The depth of the area will be 70 feet. 
  • The maximum size of an ADU will be 1,000 square feet or more. It will not include your garage in this area. You can build them in any separate space.
  • You can select any area for your floor.
  • As the landlord, you can build two ADU together in the SF zones.
  • You cannot build up a parking lot for your ADU. You will not be able to eliminate the parking made earlier for the parking off-street. You have to remove it from another parking place. 
  • You can build one or more ADU and DADU in your area if you want to. You won't be able to make more than eight leading houses and ADU in your area. If you do so, all of them should be your relative.
  • You cannot build an ADU bigger than 60 percent of your area. While building the ADU, you may need to cut trees. In that case, your ADU won't be able to cover your area's 40 percent or more than it. 
  • You will have to meet all the codes for Seattle, whether they are codes of your residential, electrical, mechanical, shorelines codes, use of the lands, and so many. 


Those are the basic rules you should follow. Otherwise, you will not be eligible to build up your ADU. Your design also needs permission. Only then can you build up an ADU. But you are free to select any design you want. 


After fulfilling all the requirements, you can build your ADU or DADU. You can use the ADU as an office for a maximum of one year. Later, you can think about renting it. Following the rules will help you minimize the cost of building the ADU or DADU. 


Enforcement Of ADU Law


The government permitted the first attached accessory dwelling units in 1994. Later, Mayor Jenny Durkan led the Seattle City Council in July 2019. He passed the new law for ADU through anonymous voting. The Seattle new ADU rules came to be on 8th August 2019, after 30 days of the mayor's sign. Thus, the landlords got many benefits from building low-cost ADU structures. You may rebuild your existing structure. Besides, you can also make a new one. You should follow all the rules and maintain the codes too. Experts like Emerald ADU Builders can build beautiful structures in such a small area. The number of ADU builders is multiplying in the area day by day. 


Advantages Of ADU Or DADU


The advantage of the buildup of more ADU already has been provided. Many people with a solution to their residential problems. Through the ADU, many people have lived in a comparatively short area. Besides, the homeowners can rent them and earn some extra money. Their empty land is becoming helpful in this way. You can also let the older people of the family live there.


Extra care for their sickness or old age is needed for them. It is an ideal place for your relatives' long day visit. They can live there according to their wish. Besides, they will have their separate entrance also. So, none of them will cross their path and feel disturbed. 


According to the consent of Seattle ADU Builders, Seattle ADU rules were made for the landowners and the benefit of the town. With the growing population, it is hard to find a new residence for them. The ADU and DADU have made that very easy. The town planner saw this advantage and passed the new law enforcing new rules. What are you waiting for? Go for an ADU and utilize your extra space!


Sources

Call (206) 222-2898 for immediate assistance.

How ADU Construction Process Works

  • 1. Send a request

    First things first - send a request to us to start the process. 

  • 2. Site Walk-through

    We will do a walk-through of your property to scope out the project and look for any issues. 

  • 3. Design & Planning

    Choose a building design and plan to the specifications of your property. 

  • 4. Permitting

    Permits in the city of Seattle are mandatory and we help you along with the process. 

  • 5. Build

    Once everything is approved we will start the building process.

  • 6. Completion

    After the build, we always do quality control and inspection for project completion.

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