What accessibility means
Structures are accessible where people with disabilities can reach and use them in the customary manner, without particular difficulty and in principle without assistance. The definition is substantially the same across all state codes.
Three elements of that definition matter for design. Each of them rules out a common substitute solution.
| Element | Meaning for design |
|---|---|
| In the customary manner | separate entrances or special routes do not suffice; the ordinary route must be usable |
| Without particular difficulty | refers to the effort of use, not to its theoretical possibility |
| In principle without assistance | excludes solutions dependent on support |
The standard series
The relevant standard series is structured by building type. It separates publicly accessible buildings from dwellings.
| Part | Scope |
|---|---|
| Part 1 | publicly accessible buildings |
| Part 2 | dwellings |
| Part 3 | public circulation and open space |
The division matters because requirements for publicly accessible buildings go further than those for dwellings and because the two serve different protective purposes. They also serve different protective purposes.
The standards are not automatically binding. They acquire binding force only through reference in state law or through introduction as a technical building provision, and frequently only in part. The article on recognised rules of technology covers that mechanism.
The statutory duties
The state codes distinguish two areas in essence. Their duties are framed to different extents.
| Area | Duty |
|---|---|
| Publicly accessible structures | accessible in those parts serving general visitor and user traffic |
| Residential buildings | a graduated duty: above a certain number of dwellings, a certain proportion must be accessible |
The thresholds and the proportion required differ considerably between states. They must therefore be checked in the code of the state concerned.
A statement without naming the state is therefore worthless here too. The article on comparing the state codes covers the spread.
Accessible and wheelchair-usable are not the same
One distinction is regularly blurred in tender documents and carries substantial cost effect. It concerns the relation between accessible and wheelchair-usable.
| Term | Requirement |
|---|---|
| Accessible | the basic standard under the code's definition |
| Wheelchair-usable | a further requirement, with larger circulation areas, wider doors and particular requirements for sanitary rooms |
For cost work the distinction is essential, because wheelchair-usable dwellings need more area per unit. Blurring the terms in a tender produces bids on different bases.
What this means for design
Accessibility is a question of design rather than of fit-out. It concerns four levels of the building at once.
| Level | Elements concerned |
|---|---|
| External circulation | approach, parking and entrance area |
| Internal circulation | lift, stairwell, corridor widths and doors |
| Dwelling layouts | circulation areas, sanitary rooms and thresholds |
| Controls | heights, reach and contrast |
Addressing it only after the design regularly leads to redesign. The requirement therefore belongs in the initial appraisal, not in the detailed design.
The link with other requirements
Two conflicts recur and must be resolved early. Both can be resolved only expensively once detailed design has begun.
| Conflict | What it consists of |
|---|---|
| Accessibility and fire safety | threshold-free transitions, door widths and escape route strategies can conflict |
| Accessibility and existing buildings | the requirements meet given geometries; the state codes provide relief for that |
Related articles
This article reflects the position of the rules at the date of checking and serves professional orientation. It does not constitute legal advice and does not replace assessment of the individual case.