As the new year begins, the SFBay ADU team takes a forward-looking approach to predict upcoming trends in the world of ADUs for 2025. We hope this guide will provide valuable insights and help you make informed decisions when selecting a modern ADU in the future. Here’s our vision for the near term, highlighting 10 key trends we anticipate shaping the industry in the year ahead.
Table of Contents:
1. Simplification of Legislation and Procedures2. Growth in Popularity and Accessibility
3. Innovative and Sustainable Designs
4. Integration of Smart Technologies
5. Multifunctional and Adaptive Spaces
6. Increased Sizes and Improved Layouts
7. Multigenerational Living
8. Buying Property to Share
9. Mono Pitched Roofs
10. Wellness Spaces
1. Simplification of Legislation and Procedures
In 2024, California introduced legislative changes to simplify the process of building ADUs (Accessory Dwelling Units). With a combination of laws outlined in Assembly Bills (AB) 2221, 68, 881 and State Bill (SB) 13, local authorities are now required to review construction applications more quickly, significantly speeding up the approval process. Standardized project requirements have been implemented, reducing bureaucracy and simplifying document preparation. Many zoning restrictions have also been lifted, allowing ADU construction in areas where it was previously prohibited, including single-story home lots. Additionally, minimum parking requirements have been waived in some cases, making ADU design even more accessible. These changes aim to save time, lower administrative barriers, and support the development of additional housing for state residents.
Building on the improvements introduced in 2024, the following trends are anticipated for 2025:
- Increased ADU Popularity: Simplified legislation and reduced administrative hurdles will lead to more homeowners opting to build ADUs for personal use or rental purposes.
- Growth in Housing Availability: ADUs are expected to make a significant contribution to addressing California's housing crisis, particularly in densely populated areas.
- Advancement of Innovative Technologies: Rising demand for ADUs will drive the adoption of new construction technologies, such as modular designs and the use of eco-friendly materials.
- Economic Impact: The expansion of ADUs will stimulate the local economy by creating jobs in the construction sector and increasing tax revenues.
- Further Legislative Improvements: Based on the 2024 experience, additional measures may be introduced, such as further automation of application processes or additional subsidies to incentivize ADU construction.
These forecasts suggest that ADUs will continue to play a vital role in California's housing policy, providing residents with more opportunities to improve their living conditions and increase their income.
2. Growth in Popularity and Accessibility
The demand for ADUs continues to rise as more homeowners recognize their versatility and value. In 2023, California experienced a significant increase in ADU construction, with 26,924 units permitted - a notable rise compared to previous years. The Bay Area alone saw 2,761 new ADUs built in 2023, more than doubling the numbers from 2020. This growth highlights the increasing popularity of ADUs as a practical solution to housing shortages.
As for 2024, data is still being compiled, but early reports indicate that the trend is continuing strongly, with over 1,300 new units already proposed. Analyzing public reports and the growing number of inquiries to our company, we project a minimum 10% increase in the total number of new ADUs across California in 2025. These figures underscore the growing accessibility of ADUs, driven by simplified permitting processes, innovative local programs, and expanded financing options. Whether used as rental units, guest houses, or additional living spaces, ADUs are solidifying their role as a cost-effective and versatile housing solution across California.
3. Innovative and Sustainable Designs
Sustainability and innovation are at the forefront of ADU design trends for 2025. Homeowners are increasingly seeking environmentally friendly solutions that reduce energy consumption and environmental impact. Features such as solar panels, energy-efficient insulation, all-electric heat pump HVAC systems and water heaters, rainwater harvesting systems, and green roofs are becoming standard in modern ADU projects.
It is also likely that the California Energy Commission (CEC) and the California Public Utilities Commission (CPUC) will introduce various initiatives and incentives to promote energy efficiency and the use of renewable energy in ADU construction. These programs may include subsidies for installing solar panels, rebates for using energy-efficient appliances, or incentives for integrating advanced energy management systems. These efforts aim to make sustainable technologies more accessible to homeowners and further drive the adoption of eco-friendly ADU designs.
In addition to sustainability, innovation in design is paving the way for more functional and aesthetically pleasing ADUs. Modular construction techniques, prefabricated components, and 3D-printed elements are streamlining the building process, reducing construction time and costs. Flexible layouts and multifunctional spaces allow ADUs to adapt to diverse uses, from living quarters to workspaces and wellness areas.
These innovative and sustainable designs not only meet the needs of today's homeowners but also reflect a commitment to a greener, more efficient future. As ADUs evolve, they are setting new standards in architectural creativity, environmental responsibility, and energy conservation.
4. Integration of Smart Technologies
In 2025, smart technologies are playing a pivotal role in transforming ADUs into highly efficient and comfortable living spaces. Homeowners are increasingly adopting intelligent systems to enhance convenience, improve energy efficiency, and ensure safety. Features such as smart thermostats, automated lighting, WiFi-connected and voice-controlled appliances, and integrated security systems are becoming standard in modern ADU designs.
The list of controls and customization options for ADUs is expanding with the integration of AI, enabling devices to function even better. For instance, Google is already implementing the Gemini app in Google Home, offering additional assistance directly on your phone. This innovation allows homeowners to control lighting, thermostats, blinds, and more by interacting with an intelligent assistant. AI-powered systems provide the benefits of home automation with natural language prompts and generative AI, making smart home management accessible even to those without technical expertise.
AI can also create personalized scripts for managing your smart home. For example, you can describe your needs, and the AI would generate a script for you. A sample scenario might be: "When the TV is turned on after sunset, dim the living room lights and close the blinds." The AI would then create a script that you can edit and use, making it easier than ever to customize your ADU's environment.
Looking ahead to 2025, we anticipate seeing even more examples of AI integration in smart management of ADUs. Well-known brands such as Honeywell, Apple, Amazon, and Google (Alphabet) are expected to lead this trend, expanding the ecosystem of smart home solutions. As these industry leaders introduce innovative tools, homeowners will have access to cutting-edge systems that enhance the functionality and usability of their ADUs, making these spaces smarter and more connected than ever before.
Energy management remains a key focus, with smart technologies enabling real-time monitoring and optimization of energy usage. Systems integrating solar panels, battery storage, and energy-efficient devices ensure seamless control and reduced utility costs. These advancements, combined with AI-driven automation, make ADUs not only more functional but also more intuitive and adaptive to homeowners' needs.
By integrating smart and AI technologies, ADUs are evolving into intelligent, self-sufficient spaces that combine modern convenience, personalized automation, and eco-friendly innovation, setting a new benchmark for future housing solutions.
5. Multifunctional and Adaptive Spaces
As lifestyles evolve, the demand for versatile and adaptable living spaces in ADUs continues to grow. In 2025, we expect homeowners to continue opting for designs that maximize functionality, allowing a single space to serve multiple purposes. From home offices and guest rooms to personal gyms and creative studios; we see ADUs are being tailored to meet diverse needs.
Flexibility is at the heart of these spaces. Features such as foldable furniture, movable partitions, and built-in storage solutions make it easier to transform rooms as needed. For example, a compact workspace can be converted into a cozy bedroom or an open living area with minimal effort. This adaptability is especially valuable in smaller ADUs, where every square foot counts.
The trend of creating independent spaces for remote work, which gained popularity in recent years, is now evolving. We have seen homeowners move away from rigidly designated workspaces toward more flexible, multifunctional environments. Instead of separate home offices, ADUs are now designed to integrate work areas seamlessly with other functions, such as living or relaxation spaces. This transformation reflects a shift in priorities, where adaptability and efficient use of space are taking precedence over single-purpose designs.
By embracing multifunctional and adaptive designs, ADUs offer homeowners the flexibility to create spaces that align with their unique lifestyles. These innovations ensure that ADUs remain practical, comfortable, and future-proof, meeting the demands of modern living.
6. Increased Sizes and Improved Layouts
The trend toward larger and more efficiently designed ADUs is reshaping how these spaces are utilized. Changes in zoning laws and local regulations in many regions, including California, have allowed for increased maximum sizes for ADUs. This shift enables homeowners to create more spacious and functional units that cater to a wider range of needs, from extended family living to rental opportunities or personal retreats. With larger footprints come improved layouts that focus on maximizing usability and comfort. Open-concept designs are becoming increasingly popular, offering seamless transitions between living, dining, and sleeping areas. This approach not only enhances the feeling of space but also allows for better natural light flow and ventilation. An important development for 2025 is the increased availability of pre-approved ADU plans on county and city websites. Thanks to California Assembly Bill No. 1332 (AB 1332), local agencies are now required to develop programs for the preapproval of ADU plans by January 1, 2025. These programs allow local agencies to review and approve ADU designs in advance, saving homeowners significant time and money. Approved plans will be published online, providing homeowners with a wide selection of compliant designs to choose from, simplifying the planning and permitting process. This initiative not only streamlines the construction process but also encourages innovation and diversity in ADU layouts, giving homeowners access to designs that meet their specific needs without the usual complexities of obtaining permits. The shift toward increased sizes, smarter layouts, and greater access to pre-approved plans reflects the growing recognition of ADUs as more than just secondary units—they are now seen as primary living spaces that offer the comfort and functionality of a full-sized home. This evolution ensures that ADUs remain versatile, livable, and aligned with the diverse needs of modern families.7. Multigenerational Living
The trend toward multigenerational living continues to gain momentum in 2025, as families look for practical and cost-effective ways to stay connected while maintaining their independence. ADUs are increasingly being used to accommodate multiple generations under one roof, providing a balance of proximity and privacy that meets the needs of modern families.
With the shift away from the remote work trend, the opportunity for families to spend extended time together has decreased, making proximity to loved ones more important than ever. ADUs offer an ideal solution, allowing adult parents to live close to their grandchildren while preserving their privacy and independence. This arrangement ensures that grandparents can actively participate in family life, share valuable time with their grandchildren, and maintain their autonomy in a private and personalized living space.
Design trends in multigenerational ADUs focus on creating flexible and inclusive spaces. Features such as separate entrances, private kitchens and bathrooms, and soundproofing between units ensure that each generation has the privacy they need while still being part of the larger household. Additionally, shared outdoor spaces like patios or gardens encourage family interaction and create a sense of community within the property.
As the demand grows for housing solutions that support close family connections, we predict that this trend will strengthen in 2025. Multigenerational living not only reflects changing cultural and economic dynamics but also highlights the versatility of ADUs in adapting to diverse living arrangements. By accommodating multiple generations, ADUs provide a practical solution that strengthens family bonds while addressing housing challenges in a cost-effective and sustainable way.
8. Buying Property to Share
In 2025, we predict a growing trend toward shared property ownership among families and friends as a practical response to rising housing costs and limited availability. This model leverages the flexibility of ADUs, where an independent living space serves as a private unit for one party while allowing co-owners to share property-related expenses like mortgages, taxes, and maintenance.
We also foresee an increase in joint land investments by family members or close friends. In this model, the land is used to build two or more separate homes, providing a cost-effective solution for those who prefer standalone properties or do not yet own a primary residence for ADU construction. This collaborative approach reduces individual financial burdens while offering a pathway to homeownership and long-term investment opportunities.
This emerging trend is particularly attractive for families seeking to live near each other, young professionals looking to enter the housing market, or retirees aiming to downsize while remaining close to loved ones. By pooling resources, homeowners can achieve greater flexibility and independence while fostering a sense of community and mutual support.
As challenges persist in housing affordability, shared property ownership and joint land investment represent innovative solutions for modern living. We anticipate these models will gain traction in 2025, highlighting the potential of ADUs and collaborative approaches to redefine traditional notions of homeownership.9. Mono Pitched Roofs
If you’ve been following us on social media, you may have noticed a new design trend that our clients have fallen in love with: mono-pitched (or single-slope) roofs. These roofs not only add a sleek, modern aesthetic to any ADU but also come with practical benefits that make them an excellent choice for future designs.
Mono-pitched roofs are often more cost-effective than traditional multi-plane designs and create the illusion of larger interior spaces—an essential feature for compact ADUs. They even allow for vaulted ceilings, adding a sense of openness and elegance to the interior.
One of the standout advantages of mono-pitched roofs is their compatibility with sustainable living. If you’re aiming for a net-zero home, their design provides ample roof area for solar panel installation, especially when oriented correctly toward the sun. Moreover, their single-slope structure simplifies the installation process for solar panels, which our clients particularly appreciate. This is especially relevant given the trend we discussed earlier, predicting increased governmental support for green energy initiatives. With incentives and programs encouraging the use of renewable energy, mono-pitched roofs are perfectly positioned to help homeowners take full advantage of these benefits.
As this trend continues to gain popularity, we foresee mono-pitched roofs becoming a defining feature of ADU construction in 2025. Their blend of modern style, functionality, and sustainability ensures they will remain a favorite among homeowners and designers alike.
10. Wellness Spaces
In our work with clients, we’ve observed a noticeable rise in the use of ADUs as wellness retreats, particularly for larger baths and saunas. Many homeowners are transforming their ADUs into personal spa-like environments, incorporating features such as infrared saunas, steam rooms, and soaking tubs. These additions allow clients to enjoy the benefits of wellness-focused spaces without leaving the comfort of their homes.
Advancements in smart home technology also support this trend. ADUs equipped with smart lighting systems can simulate natural light to enhance mood, while air filtration systems improve indoor air quality. These innovations align perfectly with the wellness-focused design philosophy, offering a harmonious blend of technology and tranquility.
Given the growing interest in health-oriented lifestyles, we anticipate that the inclusion of wellness spaces, particularly saunas and baths, will continue to rise in 2025. This trend highlights the potential of ADUs to serve as holistic, health-oriented living spaces that cater to the evolving needs of modern homeowners.
We are delighted to share our predictions for the top ADU trends of 2025 with our visitors. A year from now, we look forward to reviewing these forecasts, comparing them with the actual numbers, and reflecting on the results. It will be exciting to see how these trends unfold and shape the future of ADU design and functionality.
Remember, our predictions are built on the foundation of our extensive experience, which we are more than happy to apply to your ADU project. Whether you're envisioning a wellness retreat, a multigenerational living space, or even an area dedicated to remote work, we’re here to bring your ideas to life while tailoring every detail to your preferences. Let's work together to create an ADU that perfectly fits your lifestyle and aspirations.