The short version: Universal design is the practice of making homes that work for everyone, regardless of age or ability. The 10 principles below cover doorways, flooring, lighting, fixtures, and storage, apply them during any remodel and the home gets better at almost no extra cost.
Universal design vs accessibility vs aging in place
Three terms, often confused.
- Accessibility is meeting code standards (ADA, ICC A117.1) for users with disabilities.2
- Aging in place is the goal of staying in your own home as you age.
- Universal design is the practice of designing spaces that work for everyone, kids, adults, seniors, wheelchair users, without modification.
Universal design is the broader umbrella. Accessibility is a subset (specific code-meeting features). Aging-in-place is a use case (one of several that universal design serves).
The reason universal design wins is timing. Built into new construction or a planned remodel, it adds 1-3 percent to the budget. Retrofitted later, the same features cost 5-20x more.
The 10 principles
The official principles of Universal Design were developed at the NC State Center for Universal Design.4 The 10 below are the practical home-design subset.
1. Equitable use
The same home features serve everyone, adults, kids, seniors, guests with mobility needs. No “regular bathroom” and “accessible bathroom”; one bathroom designed to work for all.
Practical: a 36-inch-wide door instead of a 32-inch standard door. Both look the same; the wider door doesn’t penalize anyone.
2. Flexibility in use
Features adapt to different users without retrofitting. A height-adjustable kitchen counter. A pull-out drawer in the lower cabinet that doubles as an extra working surface.
Practical: lever-handle faucets work for arthritic adults, kids, anyone with wet hands. Knobs require grip strength; levers don’t.
3. Simple and intuitive use
Controls work the way people expect, regardless of experience or language. A switch at the door turns on the light; the user shouldn’t have to remember which switch goes with which fixture.
Practical: rocker-style light switches instead of toggle. Larger contrast between switches and the wall plate.
4. Perceptible information
The home communicates information in multiple ways, visual, audible, tactile. A doorbell that rings (audible) and lights up (visual) helps anyone with hearing changes.
Practical: smoke alarms with both audible alarms and visual strobes. Smart doorbell with chime, light, and phone alert.
5. Tolerance for error
Design that minimizes the consequences of accidents. A water-resistant floor so a spilled glass doesn’t damage anything. A stove with auto-shutoff so a forgotten pot doesn’t start a fire.
Practical: induction cooktops auto-shut-off when no pot is detected. Bathroom flooring with high slip resistance even when wet.
6. Low physical effort
The home doesn’t require strength to use. Lever handles, push-pull cabinet hardware, light-pull or motion-activated lighting.
Practical: cabinet pulls instead of knobs. Dishwasher with foot-activated open. Door handles that work with an elbow if hands are full.
7. Size and space for approach and use
Enough clear floor space at every fixture and seat for any user, including wheelchair users. 60-inch turning radius in key spaces.
Practical: bathroom with a 5-foot turning radius. Kitchen with a clear path between counters of at least 42 inches (60 inches if a wheelchair user is regular).
8. Continuous transitions (the “no-step” principle)
The home has no abrupt level changes, no thresholds higher than 1/2 inch, no sunken living rooms, no front-step entrance.
Practical: zero-threshold front entry from a sloped walkway. Single-floor primary living (kitchen, bedroom, bathroom). Curbless shower.
9. Even illumination
Lighting throughout the home is consistent and high-quality. Each space well-lit on its own schedule. Aging eyes need 2-3x more light than younger eyes.1
Practical: layered lighting, overhead, task, and accent. Switch positions reachable from each entry point. Motion-activated nightlights along bedroom-to-bathroom path.
10. Storage at usable heights
Most-used items stored between 24 and 60 inches off the floor. Lower cabinets are pull-out drawers, not fixed shelves. Pantry has shelving at varied heights with rollouts.
Practical: pull-out lower kitchen cabinets. Closet rods at 36-48 inches (not 70+). Pantry rollout shelves.
Where to apply each principle
Universal design touches every room. Here’s where each principle has the highest leverage.
| Principle | Highest-impact rooms |
|---|---|
| Equitable use | Bathroom, kitchen, bedroom |
| Flexibility | Kitchen, home office |
| Simple/intuitive | Light switches throughout |
| Perceptible info | Smoke alarms, doorbell |
| Tolerance for error | Kitchen, bathroom |
| Low physical effort | Doors, faucets, cabinets |
| Size/space | Bathroom, kitchen turn radius |
| Continuous transitions | Entry, bathroom, between floors |
| Even illumination | Whole house |
| Storage at usable heights | Kitchen, closet, pantry |
For specific bathroom application, see how to make your bathroom safer for aging parents.
What it costs
Universal design integrated into a planned remodel typically adds 1-3 percent to the project. Retrofit later costs 5-20x more for the same outcome.
| Feature | Cost in new construction | Cost as retrofit |
|---|---|---|
| 36” doorway | ~$50 extra over 32” | $1,500-$3,000 to widen later |
| Lever-handle faucets | ~$30 extra per fixture | Same; easy to swap anytime |
| Curbless shower | ~$1,500 extra over standard | $4,000-$15,000 retrofit |
| 60” bathroom turning radius | Layout decision, no extra cost | $5,000-$30,000 to remodel |
| Even-floor transitions | Layout decision, minor cost | Variable, often $1,000+ per transition |
If you’re planning any remodel, bathroom, kitchen, addition, pull universal design in from the start. The incremental cost is small. The retrofit cost is large.
What to do next
If you’re remodeling: bring up universal design at the design phase. A CAPS-certified contractor can integrate the principles into the project.
If you’re not remodeling: pick the cheapest 3 principles to apply now, lever handles, brighter task lighting, and de-cluttering pathways. Each is under $100 and meaningfully improves daily use.
For the bigger context, see the aging-in-place bible and the 50-item home assessment checklist.
- Universal design = a home that works for everyone, not just a specific user.
- 10 principles: equitable, flexible, simple, perceptible, error-tolerant, low-effort, spacious, transition-free, well-lit, smart-storage.
- Adds 1-3 percent in new construction; retrofit costs 5-20x more.
- Apply during any remodel, even bathroom or kitchen-only projects.