Sweetwater Spectrum

Sweetwater Spectrum is a new national model of supportive housing for adults with autism,
offering life with purpose and dignity. Designed by Leddy Maytum Stacy Architects, the 2.8-acre
site provides a permanent home for 16 adults and their support staff. The four 3,250-square-foot
four-bedroom homes include common areas as well as a bedroom and bathroom for each
resident. Sweetwater Spectrum also incorporates a 2,300-square-foot community center with
exercise/activity spaces and a teaching kitchen; a large therapy pool and spas; and an urban
farm, orchard, and greenhouse.
Autism is the fastest growing developmental disability in the United States, affecting 1 in 88
children. In the coming decade, as many as 500,000 children with autism will reach adulthood,
yet few residential options exist for them. In 2009, a group of families with autistic children,
autism professionals, and community leaders founded the nonprofit organization Sweetwater
Spectrum to create appropriate, high-quality, long-term housing for adults with autism in a way
that could be replicated nationwide. The new community is designed to address the full range of
needs of individuals with autism spectrum disorders, maximizing residents’ development and
The previously undeveloped midblock parcel lies a few blocks from the historic Sonoma Town
Square, close to public transit and bicycle trails. The new community had to be safe and secure
for the residents and staff and also provide for appropriate engagement with the neighborhood
and community through volunteer activities and outreach projects.
The design drew on evidence-based design guidelines for creating housing for adults with
autism, as identified in a research study conducted by the Arizona State University Stardust
Center and School of Architecture. Safety and security are paramount, and healthy, durable
materials are used throughout. Individuals may customize their personal living spaces to
accommodate their preferences and particular needs. Major design strategies included the
§ Legibility: A straightforward and consistent spatial organization provides clearly defined
transition thresholds between public, semi-public, semi-private, and private spaces.
§ Experiential Hierarchy: The design offers a layered or “nested” experiential hierarchy,
beginning with the individual room; expanding to a residential wing with two bedrooms and
then to the house with four residents; expanding outward to the sub-neighborhood of two
homes, the community center and commons, and the other two homes; and finally extending
to the broader community.
§ Preview and retreat: Residents have the opportunity to preview spaces and activities, and
they can access places of retreat for quiet and calm.
§ Predictability: All four homes are similar in design so that residents feel comfortable visiting
each other or relocating to a different house on the site.
§ Serene spaces: All spaces were designed to reduce sensory stimulation and provide a
serene environment. Forms are familiar, colors and finishes are subdued, and lighting is
mostly indirect.
A range of simple universal design strategies allows for generous accommodation and equal
access for all ages and abilities. Particular care was taken with the selection of the building
materials and systems to promote healthy indoor air quality, acoustical control, and comfortable,
super-efficient HVAC systems. Since ceiling fans can be a negative stimulus to people on the
autism spectrum, a radiant slab heating and cooling system was used with a low-velocity
ventilation system.
Targeted to meet U.S. Green Building Council LEED Gold standards, the project is also a PG&E
Zero Net Energy Pilot Project and is designed to produce onsite all the energy required to
operate the buildings.
The site was designed to maximize passive solar orientation, daylight, and natural ventilation.
All buildings incorporate photovoltaic solar panels and solar hot water. Other energy-saving
strategies include high R-value insulation in walls and roofs; high-performance insulated
windows; low-reflective “cool” roofs; solar tube skylights at interior halls; sun control where
needed with overhangs, trellises, and operable exterior sunshades; high efficiency air-to-water
heat pumps; energy-efficient light fixtures; Energy Star appliances; induction cook tops; and a
building management system. Overall, these strategies improved energy performance by +30%
better than California Title 24 energy requirements.
Low-flow plumbing fixtures throughout reduce water consumption. An on-site well was drilled to
supply water to all site irrigation systems, including site landscaping and the organic farm and
orchards. Drought-tolerant plants minimize irrigation needs, and permeable paving and
bioswales manage stormwater.
Other sustainable aspects include renewable building materials, low-VOC and nontoxic
materials and finishes, and the recycling of construction waste.
Architect: Leddy Maytum Stacy Architects


Project Type


Sonoma, California, United States

Related links


  • Leddy Maytum Stacy Architects, Inc.
  • Marsha Maytum, FAIA, LEED AP BD+C - Principal In Charge; Bill Leddy, FAIA, LEED AP - Consulting Principal; Christopher May, AIA, LEED AP BD+C; Gregg Novicoff, AIA, LEED AP BD+C; Vanna Whitney, AIA; Claudia Merzario; Andrew Hamblin
  • Sweetwater Spectrum
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