ADU: common questions and answers


Accessory Dwelling Units (ADUs) are becoming more popular as people look for ways to make side income to help with their mortgage payment or add aditional living space for their family. Per Freddie Mac, about 1.4 million properties in the United States have Accessory Dwelling units. 

If you're considering building an ADU, you should know a few things first. In this post, we'll answer some common questions about ADUs to clear up your confusion about ADUs. 

What is an ADU?

ADU stands for accessory Dwelling Unit - a secondary, smaller dwelling on a an existing single or multi-family building. They are often used as rental units, in-law apartments, or guest houses. Most places have restrictions on what qualifies as an ADU - for example, they often have to be smaller than the primary dwelling on the property and can't be sold separately. However, they can be a great way to add extra income or living space to a property without going through the hassle (and expense) of building a "new construction" house vs an ADU.

What’s the difference between ADU vs. JADU?

The key difference between an ADU and JADU is the size. A JADU is smaller, typically 500 square feet than an ADU. An Accessory Dwelling Unit (ADU) is located on the same property as a single-family home. They are often used as rental units, mother-in-law apartments, or guesthouses. On the other hand, a Junior Accessory Dwelling Unit (JADU) is a smaller unit located within the confines of an existing single-family home. They are often used as office space, art studios, or rental units. 

ADUs generally require more zoning and building permits than JADUs and tend to be more expensive to construct.

What are the different types of ADU?

ADUs comes in various forms. Based on your needs, budget, and space, you can build any type of ADU. Here are the most common types of ADUs:

Attached ADUs

An ADU attached to the main house or structure is called an Attached ADU. It is an addition to the existing house or the conversion of extra space in the house to an ADU. This type of ADU is a popular choice as more and more people are considering the conversion of their basements into an ADU. This provides them with extra space that can be utilized for several different purposes. 

An attached ADU typically does not require a setback and can be as tall as the primary house. One thing that makes an Attached ADU an ideal choice is that it is very cost-effective compared to a Detached  ADU. This type of ADU is suitable for compact lots that have less space. 

Detached ADUs

A detached ADU is a separate living area that basically acts like a standalone apartment. Since it is entirely separated from the Main property, it requires its electric supply, plumbing, and other things that an apartment needs. 

It is typically built in the backyards of homes and is known as "casita", backyard home or guest house. The main benefit of a detached ADU is that privacy is not compromised, and it can be rented out as independent living quarters to generate passive income. You need to have sufficient space to build a Detached ADU. Most cities do require setbacks (4 feet space at rear and side) and have height limitations (height must not exceed 16 feet), but they are still larger than Attached ADU.

Garage conversions

You can also convert your garage into an ADU; this type is called a Garage conversion ADU. This can be a great way to make the most out of your garage. Such ADUs offer different benefits like saving money and providing extra living space; they can also be given on rent and will provide passive income. Building an entirely new home requires not only more time but also more money. Converting your garage into an ADU is a budget-friendly method that provides all the benefits of a separate living. It is a full-blown living space with a bedroom, bathroom, kitchen and living room area. 

What are the benefits of building an ADU?

There are many benefits to building an ADU. First, they can provide additional income by generating rental income or freeing up space in the primary residence that can be rented out. Second, they can provide flexibility in housing arrangements, allowing homeowners to age in place or accommodate live-in caregivers. 

Third, they can improve the resale value of a home. ADUs can add up to 35% to your home’s value. And fourth, they can help to reduce the demand for new housing units, which can help to preserve green space and reduce congestion and pollution.

If you're considering building an ADU, check with your local zoning regulations to ensure it complies with all applicable laws.

How long does ADU permitting take?

Before starting the construction of an ADU, you need to get a permit. The process of obtaining a permit for an ADU can vary widely depending on the property's jurisdiction.

In some jurisditcitons, the process may be more complex, requiring multiple in-person meetings with planning officials. Regardless of the specifics, it is essential to factor in the time needed to obtain a permit when planning to build an ADU. While the timeline can be challenging to predict, most experts agree that the permitting process for an ADU can take anywhere from 4 to 6 months.

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