Housable ADU Project Case Study:
Design Challenge: In addition to the undersized lot, this property was also located in a flood zone. Because the primary dwelling was not built to the current FEMA standards the entire structure required elevation to above base flood levels. This project was also designed prior to the more recent ADU laws and had increased setback requirements limiting placement options.
Process and Solution: The customer chose to build an attached ADU, raise the entire building including the new ADU to above the base flood elevation, and keep their existing garage for parking. The property owner was actively involved in this project and worked with their contractor and the city to ensure that the final project met FEMA requirements.
Our design team modified the homeowners ADU concept to meet the ordinance requirements as well as FEMA standards. Since construction costs did not exceed 50% of the primary home value, no flood-related updates were necessary for the primary home outside of raising the structure to above the base flood elevation. The final ADU included two bedrooms, a separate living area, a full kitchen and dining room, two bathrooms, and a standing washer-dryer set.
Unique Project Traits: The entire structure, including the existing primary dwelling, required elevation above flood levels and specific flood resilient materials. Foundation vents were added to the new structure but were not required for the main home. The city also required additional material details for the connection between both structures.
See an early ADU Design for the project below. Customers may provide mark ups to request changes and confirm information about their project throughout the process.
To get started, confirm what you can build on your property with a free ADU Property Report: