Although Ancillary Housing Units (ADUs) play an important role in society as a whole, they ultimately exist to provide people with a healthy and safe home. This article focuses on the last of these two purposes – how to design ADUs that best meet the needs of residents. As the last in a two-part series on ADUs, this article aims to give Evanston a more comprehensive understanding of why and how you or your neighbor will take on the ADU project.
Like any project, you should start your ADU with a goal. Why is it built and for whom is it built? In many cases, ADU is used in many ways over time. They can work as an apartment renter or family member for years, only to become a home business during a career transition, as in a recent RoundTable article about a bike repair shop in a bike repair garage. It is helpful to have a clear understanding of both the primary and initial purpose of the chassis as well as the use cases required over time, as this greatly affects the type of ADU that makes the most sense for you.
Then, time and money can be saved to reach the budget scope of the ADU project early. Otherwise, you may end up designing a unit that doesn’t fit within your budget range, which may require a redesign. While it’s tempting to search for “dollars per square foot ADU cost” on the Internet, it can often be difficult to compare apples to apples. Different types of ADU usually have different cost ranges, and expenses such as utility connections or permit fees can sometimes be excluded from estimates.
To get an initial idea of ADU’s costs, AARP’s “ABCs of ADUs” cite construction costs below the images of the various ADUs in the guide. If you are a homeowner, it may be helpful to speak with the mortgage holder on your primary home, or a trusted financial advisor, to understand your financing options. This step ensures that residents design a project that not only meets their living needs, but one that they can eventually afford to build.
Once you have a consistent sense of the project’s purpose and budget scope, this can be a good time for you to get a feel for the type of ADU.
While most people usually think of a ‘detached’ independent Abu Dhabi unit in the backyard, ADUs can also be part of an existing primary residence. It can be “inside” (for example, transforming an existing space in the house) or protruding outside the main house. Finally, as is common in Los Angeles, it could be a garage conversion. Each of these options has its pros and cons, which are explained in a more nuanced level of detail in the city publication Evanston’s Guide to Accessory Dwelling Units.
During the architectural design process, compliance with Evanston’s zoning and building rules will affect the design of your project. Fortunately, Evanston has a relatively flexible ADU token. Your “zoning area” is the primary variable in this equation. Anyone can find property zoning at Evanston 311 About My Place. Zoning area affects several things, including the permitted amounts of “building area coverage” and “impervious surface coverage” on your property.
While “building area coverage” determines the amount that buildings can occupy (as opposed to vacant land), “impermeable surface coverage” regulates the percentage of hard surfaces (eg, rooftops, concrete driveways, etc.) that can occupy a property. . Coverage of building area and impermeable surface coverage together will be key zoning policies that define the shape and size of ADU. Regardless of your partition area, new ADUs can only fit up to 1,000 square feet of living space.
Three additional zoning issues that require consideration are setbacks, elevation, and parking. Setbacks refer to the distance an Abu Dhabi unit can be from an ownership stake line or primary place of residence, requirements vary by type of structure and zoning area. As for height, one can go up to 28 feet with a sloping roof, providing flexibility in the design. Finally, one is not required to add additional off-street parking space when building an ADU in Evanston, which opens up design options, but you cannot permanently reduce parking spaces. If you remove an off-street parking space during the Abu Dhabi University project, when the project is completed, you must have the same number of off-street parking spaces on the property.
Finally, there are two specific issues that deserve attention while designing ADU: accessibility and sustainability. According to a study by Harvard University’s Joint Center for Housing Studies, only 1% of the current housing stock has all the key features needed for accessibility. If an individual is building an ADU for elderly parents or a disabled relative, it may be important to consider accessibility from the start. Due to the relatively lax regulations for off-street parking in Evanston, an ADU can often be designed at ground level. In addition, one can plan wider entrances and corridors with zero pitch; futuristic designs in bathrooms; and accessible light switches and outlets, to name a few.
With climate action needed to swell, new ADUs are also an excellent opportunity for more climate-resistant buildings. These structures can be completely electric without relying on natural gas. Incorporating highly efficient appliances can save energy and money. For example, an induction stove, an electric oven, an air source heat pump for space heating and cooling, a hot water heat pump water heater, as well as a heat pump clothes dryer can contribute to a potentially net zero carbon buildup.
Additionally, the ADU can be highly airtight and highly energy efficient, keeping heating and cooling within the building’s airtight envelope. Combined with an energy recovery ventilator that constantly replaces old indoor air with fresh outdoor air while retaining air temperature, the Abu Dhabi unit can efficiently provide clean and healthy air with minimal energy use. Furthermore, it can be relatively inexpensive to add electric vehicle charging to a garage or garage.
ADUs are exciting because in a relatively small space, there is an abundance of design opportunities for a future home – a conversion of an underutilized part of the house, a garage or a new backyard space.
Whatever their purpose, ADUs require a time commitment to site analysis, architectural design, building drawings, permit and construction review. However, if the finished structure corresponds to the owner’s vision and needs, then ideally it is worth the effort. Even better, it’s another condominium in a city with limited supply, and hopefully a welcome addition to the neighborhood.
Evanston design articles “Eye on Evanston” focus on Evanston’s design history and advocate good design. Visit designevanston.org to learn more about the organization.
