You may have extra room on your property. So, you might be thinking about building an accessory dwelling unit (ADU). An ADU is a secondary housing unit and it shares the lot of or is attached to your primary residence. People also refer to them as guesthouses, mother-in-law suites, or even granny flats. Essentially, as the alternate names imply, an ADU offers a way for you to provide additional living space to guests or family members.
Are there different types of ADUs?
Regulations for ADUs depend on your location within the Greater Austin area, so you need to check local zoning laws prior to building. If you aren’t sure where to even begin, having a consultation with a general contractor will put you on the right track. Three types of ADUs that a design-build company in Austin is generally able to construct are:
- Detached ADU: This is a standalone unit that is separate from your primary residence. It is the best option if you are planning to rent your ADU for passive income.
- Attached ADU: This addition is connected to your primary residence. It will often come with its own entrance on the side or back of the unit.
- Over-Garage ADU: This is an addition to the second story, limited to 550 square feet. It is also possible to build a two-story ADU which has part of the unit next to the garage, on the first floor.
What is the construction process like for ADUs?
Make sure to hire a skilled contractor that has experience in building ADUs, specifically, so that you have a smooth experience from start to finish. When talking to your contractor, provide them with your budget, design ideas, and needs for the space. Take all of this into consideration when designing your ADU.
Photo by Chewy on Unsplash
Is it expensive to construct an ADU?
It is difficult to determine an estimate for an ADU because several factors contribute to the cost of construction. There is the size of the unit, the materials used, the cost of utility connections, and the type of ADU you want. The most expensive ADU option, however, is over-garage. The reason for this is that your general contractor will have to make the garage structurally sound before building above it. Most garages are not built to support a second story, so a design-build professional in Austin will have to perform some extra labor.
Note, too, that ADUs tend to cost more in Austin than they do in other major Texas cities, like Houston and Dallas. This is because there are more regulatory barriers.
What does Austin expect from ADUs?
You might be surprised to learn that home values in Austin have increased by 99% in just the past five years. For this reason, homeowners have become eager to build ADUs. Back in 2015, the city of Austin passed a more forward-thinking ADU ordinance. A design-build company in Austin should be knowledgeable about these current requirements:
- The maximum size of a lot for an ADU on SF-3 zoned lots is 5,750 square feet
- Parking must be added alongside the parking requirements for the primary residence
- The maximum size of an ADU is 1,100 feet or 0.15 FAR (depending on which is smaller)
- An ADU must be separated from the primary residence by a minimum of 10 feet
- You cannot build an ADU if your property has deed restrictions
- You cannot build an ADU if you have trees or utilities in the way
What features should an ADU have?
Will an ADU make my home more valuable?
Because an ADU offers greater flexibility for multi-generational families, it can certainly increase the value of your home. According to a study in 2021, ADUs are able to add 35% to your home’s value! Of course, that value is going to depend on various factors, including the location, size, and quality of your ADU. We recommend simply keeping an eye on the market. But considering how affordable they are in the long term, these units make for a much-needed housing solution during the housing shortage.