A framework with seven parts
Universal design is a set of principles developed in the 1990s by a group of designers and researchers who wanted a shared way to describe products and environments that work for as many people as possible without special adaptation. The framework is usually summarized as seven principles. They were written for products and buildings, but planners often borrow them for streets and services. This article walks through each principle, shows how it might apply in a city, and then looks at where the framework is less helpful.
The seven principles in a city setting
1. Equitable use. The design is useful to people with diverse abilities, and nobody is separated or stigmatized. In a city, this suggests one main entrance for everyone rather than a ramp around the back, and a transit fare system that works for people with and without smartphones.
2. Flexibility in use. The design accommodates a range of preferences and abilities. A plaza with both steps and a gentle ramp, or benches at several heights and with and without arms, offers choices. A street crossing with both a push button and an automatic detection option is another example.
3. Simple and intuitive use. The design is easy to understand regardless of experience, language or concentration. For cities, this points to consistent street signage, clear layouts that do not need a map, and public services with plain forms and simple instructions.
4. Perceptible information. The design communicates necessary information effectively, whatever the user’s sensory abilities. Think of pedestrian signals that both show a symbol and make a sound or vibration, station announcements that are both spoken and displayed, and tactile cues at crossings and platform edges.
5. Tolerance for error. The design minimizes hazards and the consequences of mistakes. Examples include handrails on both sides of a stair, non-slip surfaces, platform edges with clear warnings, and ticket machines that let a person correct an entry without starting over.
6. Low physical effort. The design can be used efficiently and comfortably with little fatigue. Automatic doors, gentle slopes, level surfaces and seating along walking routes belong here. So do shorter distances between everyday destinations.
7. Size and space for approach and use. Appropriate size and space is provided for approach, reach and use, regardless of body size, posture or mobility. That means wide enough sidewalks, clear floor space beside benches, counters at usable heights, and turning room at doors and ramps.
Applying the principles to a street
Imagine a single block. Under universal design thinking, planners would look for a continuous, wide, level walking path; corners with well-aligned curb ramps; crossings with audible and visible signals; bus stops with clear space; benches at intervals; lighting that reveals the path; and clear, high-contrast signs. Each of these can be traced to one or more of the principles. The value of the framework is in providing a checklist of questions rather than a set of dimensions.
Where the framework falls short
Universal design has been influential, but it has recognized limits.
- “For everyone” is aspirational. No design works for all people in all situations. Some needs conflict, such as a flush crossing that helps wheelchairs but removes the curb edge many blind pedestrians use as a cue. The principles give little guidance on how to resolve such conflicts.
- Principles are not measurable standards. They are broad statements. Two designers can apply them differently, and a project can claim to follow them while still leaving gaps. Technical standards and local codes, which vary by place, are still needed for specifics.
- Limited attention to process. The principles describe features of a design, not how it was made. They do not require that disabled people or other users be involved, which is why many practitioners pair universal design with inclusive design processes.
- Cost and existing buildings. The framework is easiest to follow in new construction. In older areas, full compliance may be unaffordable or impractical, and designers settle for partial improvements.
- Context and culture. What counts as intuitive or comfortable differs across cultures and places. A design that works in one country may need adaptation elsewhere.
- Beyond the physical. Services depend on staff, policies and digital systems as well as buildings. The principles can be stretched to cover these, but they were mainly shaped by thinking about physical objects and spaces.
Using it sensibly
For planners and community members, the principles work well as a conversation starter and a review tool. At design review, someone can ask of a proposal: Does it separate people? Does it offer options? Is the information available in more than one form? What happens if someone makes a mistake? Is there enough room? Posing these questions early tends to uncover problems that would otherwise surface only after opening.
Used alone, though, the framework is not a guarantee of success. Real results depend on testing with people, careful maintenance, funding and the local rules that apply.