We believe the easiest and highest quality ADUs are detached, new construction projects. Having space between the ADU and the main house provides privacy, allows for flexibility in the future if you decide to divide the lot or sell each unit separately, and allows the most flexibility in terms of design and layout. We also find that new construction gives you the highest quality project and allows for a sustainable, high-performance building. We don’t recommend garage conversions and don’t do renovations or basement conversions either. We focus specifically on new construction, detached ADUs.

The first step is to find out if your city or municipality allows Accessory Dwelling Units (ADUs). Some states, like California allow ADUs statewide. Oregon and Washington also have laws that are very supportive of ADUs across the state. However, check with your local building department to determine you local rules.

If they are allowed, you'll need to learn about the regulations surrounding them - for example, minimum size requirements, lot coverage limitations, height restrictions, and setback rules. For instance, in California ADUs have side and rear setbacks of 4' consistently, and you should factor in 6’ to 10' separation from existing structures.

You'll also need to choose a location on your property for your ADU and develop a site plan. Once you've done your research and found a suitable spot on your property, you can begin planning your project.

If you're not sure where to start, we offer consultations for those who want to ask questions. This is a great way to talk through the best path to meet your needs. Whether it is a custom design for those who are looking for a unique and luxury ADU solution, or pre-designed ADU plans that can save you time and money, a consultation can help you start the project off right and ensure you are on the best path forward.

Our ADU budget advice:

If you want a truly beautiful and sustainable project you probably should budget upwards of $100,000 for your ADU. This will get you a project that uses premium materials, and high performance systems; one that you will be proud of, will be durable, and will add a lot of value to your property. We have found that ADUs are great investments and you recoup the cost of building through rental income, increased space for your family, and increased property values.

Tons of people have come to us asking for garage conversion ADUs over the years, and the majority of the time my recommendation is to tear down the garage and build a new detached ADU. Doing an ADU garage conversion can be rather expensive for what you end up with, and probably won't get you what you are looking for.

Sometimes conversions actually cost more than building new considering you would most likely have to redo the foundation footings and concrete slab, plus add sewer and water to the right places. Working within an existing structure makes all of this a lot more complicated and thus costly.

Also, most garages were not built to meet current building codes for housing so require a lot of rebuilding and adapting to meet the codes as well as be a nice place to live. Plus working within an existing footprint can be very limiting. You may get a higher return on investment by building new and going with a larger ADU than trying to squeeze it into the footprint of an old garage.

And if you do build new, you could potentially put an ADU over a new garage. Having a two bedroom rental over a 2-car garage is a great way to preserve some private off-street parking while generating rental income, or downsizing.

We sure do think so. In fact, we have added an ADU to a house we owned and would have added additional ADUs if the local regulations allowed it. Generating rental income was a great ROI for our ADU.

Of course the answer to this question depends a lot on your situation and finances. In general, ADUs are great investments in that they can generate income as a rental unit or save you thousands of dollars a month on costly housing for aging family members or for yourself. On top of rental revenue or savings on housing costs, ADUs also increase your property value if or when you decide to sell your property. Often the increase in value to your property is more than the cost of constructing the ADU. They are well worth the investment and can both generate passive income as well as increase your home value.

Congratulations on being ready to purchase an ADU house plan. Since every site is unique and each local jurisdiction has their own set of rules and regulations, you will need to do the due diligence to make sure the design you purchase is allowed and will work on your property. You also need to get structural engineering and/or engage other consultants to provide any information your local regulations require. We also recommend that you hire a local designer, architect, engineer, and/or general contractor to develop the site plan, to assist with the permitting process, and help make any design revisions you may want (although you can also contract with us to make simple design changes.

Once the casita design has been permitted and approved by your local building department, you will also need someone to build the ADU. Although you could DIY it, we find that most people would be better served by hiring a licensed General Contractor to construct the ADU. A good builder can really help make your project a success.