ADUs: Before You Build Checklist

ADUs, or accessory dwelling units, have become increasingly popular in recent years for a variety of reasons.  Having an ADU can provide extra living space to keep an aging family member nearby, serve as a “starter home” for young adult children or provide bonus rental income to help offset your primary residence.  ADUs are especially popular here in the Bay Area as a cost-effective solution to help increase the supply of affordable housing opportunities.  

As more and more cities, counties and other municipalities are providing incentives and relaxing zoning laws making it easier for homeowners to construct an ADU, the timing might be right to consider building an ADU on your property.  But before you run off to your local Planning & Permits Department, give some thought to how you might want (or have!) to address these 10 factors which may affect the size, cost, design and timing of your build: 

1. Zoning laws: Make sure that building an ADU is allowed in your area and that you meet all the zoning and building codes regulations.  Most City and County websites now have dedicated “how-to” pages specifically addressing their application and approval processes and requirements. 
2. Cost: The cost of building an ADU can vary greatly.  Options exist for those seeking no-frills, prefab, low budget units all the way up to entirely custom built, high-end, luxury designs.  Consider how and why you intend to use the ADU, and what level of quality, comfort and amenities you need or desire. Be sure to clarify exactly what is included/excluded when comparing bids, and if material/labor costs are fixed or variable.  Determine your budget upfront and be sure to maintain ample reserves in case unexpected delays, repairs or design challenges develop at some point in the project. 
3. Size and design: Consider the size and design of the ADU to ensure that it complements your existing home and fits within your property lines according to setbacks mandated by local zoning laws.  Codes may also limit the maximum square footage of an ADU relative to the size of your primary residence.  Check with your local Planning Department to determine the guidelines applicable to your particular lot. 
4. Parking: If building an ADU will add additional persons to your property who own a vehicle, consider where their parking space(s) will be located.  It's important to have a game plan to ensure sufficient parking exists for both the primary residence and persons occupying an ADU.  Check with your local Planning Department to decipher if directing ADU residents to use street parking is sufficient, or if space(s) must be provided for on your lot.  
5. Accessibility: Depending on your municipality and the intended use of your ADU, there may be design build requirements to comply with the Americans with Disabilities Act.  Check with your local authorities to determine your requirements. 
6. Utilities: If feasible, it is recommended that the ADU has its own separate utilities, such as electricity and water, to avoid any conflicts with the main house.  Many ADUs are capable of being built with eco-friendly or other “green” features, such as solar panels and energy-efficient appliances, to reduce their environmental footprint and lower overall utility costs.
7. Insurance: Make sure your homeowner's insurance policy covers the ADU and that you and your tenants have the proper insurance policies in place to protect each party's respective assets.
8. Maintenance: Consider the ongoing maintenance, upkeep and systems/appliances replacement costs that will be required over time for your ADU.  Remember to factor those additional expenses into the household budget of your primary residence.
9. Privacy: Consider the privacy of both the ADU resident(s) and the primary residence, ensuring that the ADU has its own private entrance and separate outdoor space (if possible).  It is advantageous to position the ADU or create landscaping so that each entity feels they have their own area not in direct view of one another.  
10. Financing:  Are there grants or incentives available through the State, City or County to help cover pre-development or construction costs?  Will you be paying cash or drawing upon the equity in your primary residence to fund this project?  Financing options for ADUs are available, so check with your local lender to determine what sorts of lending products best suit your needs.  

By keeping these factors in mind when designing and building your ADU, you can ensure that the unit is functional, attractive, and effectively meets the needs and desires of everyone using it. 

For more information about ADUs, or to be introduced to a trusted, local ADU design builder or lender, contact Stephanie Hevezi at 510.410.9802 or email [email protected].