Tread depth
The width of the horizontal part of a step — the support area for the foot. The optimum for a home is 27–32 cm.
01 /Main depth standards
The tread depth (the width of the horizontal part of a step) determines the support area for the foot when walking. The ideal standard for a home is 27–32 cm (270–320 mm). At this size an adult's foot rests fully on the step, which ensures safety.
- 🛏️ 32–35 cm. A very comfortable, gentle step. Requires a lot of space for the flight.
- 🏡 27–31 cm. The optimal range. Provides maximum comfort when climbing and, more importantly, a safe descent.
- 📐 25–26 cm. The minimum acceptable limit for main living areas. When descending, the heel or toe will slightly overhang.
- 🪜 Less than 25 cm. Used only for auxiliary stairs (attic, basement, spiral).
02 /Ways to increase depth (overhang)
If space is limited and a full tread cannot be fitted into the design, an overhang (nosing) is used — the upper step overhangs the lower one.
- Recommended overhang for wooden steps: 2–3 cm.
- Maximum overhang: 4 cm (any more and the toe will catch on the way up).