For decades, accessibility in public spaces has largely been measured by what people can physically enter and use. Ramps, elevators, accessible restrooms, and wider doorways are essential parts of that conversation. But what happens after someone gets through the door? For a neurodivergent person, a technically accessible building can still be extraordinarily difficult to use.

Fluorescent lights may flicker or hum. Conversations, music and machinery can compete for attention. Signs may be unclear, layouts may be confusing, and crowds may be unpredictable. There may be nowhere to escape the stimulation without leaving altogether.

That gap is prompting architects, researchers, psychologists and neurodivergent advocates to reconsider what accessibility should mean, particularly as research examines how the built environment affects autistic and other neurodivergent people.

Jack Chaffin, AIA, partner at Johnston Architects , believes the definition needs to grow.

"Traditional accessibility standards have primarily focused on physical access: whether someone can enter, move through, and use a building," Chaffin says. "That work is essential, but it does not fully address whether a person can comfortably understand, tolerate, and engage with the environment."

Neurodivergent Accessibility Goes Beyond Getting Through The Door

Sensory barriers can be easy to miss when they do not affect you personally. For someone who is particularly sensitive to sound, the persistent hum of equipment or overlapping conversations can become exhausting. Lighting that seems ordinary to one visitor can be painful to another. Even navigating an unfamiliar layout can require significant cognitive effort.

"A building may be accessible by code and still be functionally unusable for someone who becomes overwhelmed, disoriented, or exhausted by it," Chaffin explains.

Licensed psychologist Jacqueline Shinall makes a similar distinction. Bright or flickering lights, competing sounds, strong smells, crowds, unclear signage, and unexpected interactions can consume so much of a person's energy that participating in whatever brought them into the space becomes considerably harder.

That experience can have serious consequences in certain environments.

Dr. Gemma Williams, an autistic academic whose research has focused on sensory environments in public spaces, points to research examining the experiences of young autistic people in long-term mental health inpatient care . Smells from canteens and laundry rooms, constant alarms and medical equipment, and bright overhead lighting could contribute to an escalation of dysregulation. Williams notes that this could lead to restraint and isolation procedures, potentially creating further harm.

Related research into sensory experiences and reasonable adjustments in mental healthcare environments adds to a growing case for treating sensory experience as an important component of accessibility.

For Chaffin, that raises a broader question for the profession. Rather than simply determining whether someone can maneuver safely through a building, he wants designers to consider whether a person can understand where they are, regulate their experience, participate, and remain there with dignity.

Neurodivergent Design Needs Choice More Than A Perfect Formula

There is a catch, and it is an important one: there is no universally soothing sensory environment.

Neurodivergent people do not all have the same needs . One person may crave quiet while another regulates through sound. Dim lighting may help someone with light sensitivity, but it can create difficulty for someone who needs a brightly illuminated environment.

Williams sees this as one of the central challenges of neuroinclusive design. She points out that many neurodivergent people are hypersensitive to bright lighting, while some people with dementia or visual impairments may benefit from brighter spaces. Even among autistic people, sensory preferences can conflict.

That makes choice especially valuable.

Shinall says practical changes can include quieter areas, predictable layouts, clear signage, adjustable or softer lighting, reduced background noise, and places where someone can temporarily retreat and regulate. Yet she cautions against assuming that designers can create a single perfectly "sensory-friendly" environment.

"Giving people more choice and control over their environment is often more useful than trying to create one perfectly 'sensory-friendly' space," she says.

Britne Jenke, CPACC, also points to sensory zoning and intuitive wayfinding as important strategies because they give people more autonomy over their surroundings. She cautions that neuroinclusive design can become superficial if it consists primarily of a separate sensory room removed from the main public space. Greater flexibility around lighting, sound, and seating can instead be incorporated into the places everyone uses.

Chaffin would like to see that philosophy become common practice, with different sensory conditions available throughout a building, intuitive circulation, fewer unnecessary visual and acoustic stressors, and places where people can pause without being forced to leave.

Guidance on sensory-friendly LED lighting in healthcare environments offers one example of how specific elements of the built environment can be reconsidered through this lens.

Neurodivergent People Should Be Part Of Designing Neurodivergent Spaces

Perhaps the most consequential change has less to do with architecture itself and more to do with who gets invited into the design process.

Chaffin's research includes finding ways for non-speaking and differently communicating people to evaluate environments without depending solely on conventional interviews and surveys. That may include visual scales, images, gestures, spelling boards, supported communication, observation, or allowing participants to revisit a space before responding.

"One of the most important lessons is that a person's ability to describe an environment verbally is not the same as their ability to perceive or evaluate it," he says.

That distinction matters. A traditional interview can inadvertently favor someone who can quickly turn a complicated sensory experience into spoken language. The person most affected by an environment may consequently have the least accessible way to comment on it.

Chaffin's team is also pairing participant feedback with measurements of conditions such as sound and light. He emphasizes that the measurements are meant to provide context for participants' reports, rather than replace their experiences.

Shinall similarly argues that participation should begin before major decisions are made. That means including people with diverse communication styles and support needs, offering multiple ways for them to express their preferences, and compensating them for their expertise.

Jenke puts it even more plainly: neurodivergent and differently communicating people should be involved from the initial architectural brief, with co-design and paid advisory roles occurring before blueprints and budgets are finalized.

Neurodivergent Inclusion Means Designing For People Who Aren't The "Average"

Dr. Daniel Wendler, an autistic psychologist specializing in autism, sees another opportunity in moving away from accommodations that separate neurodivergent people from everyone else.

Many everyday environments were never created with neurodivergent sensory or cognitive needs in mind, he says. Sudden or persistent noise may be overwhelming. Strong smells can become intensely unpleasant. An autistic employee may struggle in a workplace where expectations change constantly, while an employee with ADHD could find an environment requiring long stretches of uninterrupted attention especially difficult.

Communication itself can become an environmental barrier. Indirect instructions, unexplained social rules and vague deadlines all require people to infer information that could simply be made explicit.

For Wendler, the strongest design solutions allow neurodivergent people to participate in the same spaces as everyone else, rather than directing them into separate areas.

That philosophy overlaps with Williams' description of Universal Design. The objective is not to find a single solution that satisfies every person. Individual accommodations will still be necessary. Instead, she describes an approach that rejects designing around an imagined average person and tries to account for the broadest possible range of human needs from the beginning.

Her point echoes philosopher Thomas Nagel's famous exploration of the limits of imagining another creature's subjective experience in "What Is It Like to Be a Bat?" . However empathetic a designer, architect, or policymaker may be, it is difficult to imagine someone else's embodied sensory experience fully.

The better alternative is to ask.

Neurodivergent-Friendly Public Spaces Could Benefit Far More People

Formal accessibility standards may eventually address issues such as lighting quality, acoustics, wayfinding, environmental predictability, and places for sensory refuge. Chaffin does not expect that to result in a simple checklist, because the variation among neurodivergent people makes that approach inherently limited.

Instead, he sees the goal as creating spaces that are easier to comprehend and offer meaningful options for those who use them.

That shift could change what we mean when we call a building accessible. A person may be able to enter a museum, hospital, school, airport, office or government building and still spend the entire visit fighting the environment around them. Physical access gets them inside. Sensory, cognitive and communication access may determine whether they can stay.

Designing with neurodivergent people from the beginning cannot eliminate every barrier for every person. It can, however, replace assumptions with choices, make participation easier, and acknowledge something architecture has sometimes overlooked: that entering a space and belonging there are two very different things.