A shallow staircase has a gentle pitch: the steps are low (small rise) and deep (large going), so you walk up with a natural stride. In Dutch it is called a luie trap, literally a lazy stair. The opposite is the steep stair, where you have to lift your foot high and cannot place it fully on the tread.
The price of comfort is floor space: a shallow stair needs a longer run, because covering the same floor-to-floor height takes more steps and each one is deeper.
The step formula
Whether a stair walks well depends not on rise or going alone but on the combination. The classic rule is:
> 2 × rise + 1 × going = 550 to 700 mm
That range reflects the length of an average stride. A stair that follows it climbs in a natural rhythm.
| Type of stair | Rise | Going | Character |
|---|---|---|---|
| Steep domestic stair | around 200 mm | around 220 mm | Space-saving, tiring |
| Comfortable stair | around 175 to 185 mm | around 250 mm | Pleasant in daily use |
| Shallow stair | around 150 to 165 mm | around 280 to 300 mm | Generous, easy with luggage |
What the regulations require
For a private stair in a dwelling, Approved Document K in England sets a maximum rise of 220 mm, a minimum going of 220 mm and a maximum pitch of 42 degrees. Note that you cannot combine the maximum rise with the minimum going: that gives 45 degrees and fails the pitch limit. Headroom of 2.0 m above the pitch line is required. Other jurisdictions have their own figures, so check the rules in force where you build.
These are minimum requirements, not targets. A shallow stair sits comfortably beyond them and is therefore always permitted — if you have the space.
When is a shallow stair worth it?
- Accessible and lifetime homes — as leg strength declines, the rise is the deciding factor
- A stair you use daily carrying things — laundry, a child, shopping
- Cellar and loft stairs you want to use as a full stair
- External and garden steps — outdoors people naturally walk with a longer stride
Practical tips
- Measure the available stairwell opening first — it sets the number of steps and therefore the rise. Divide the floor-to-floor height by the number of risers
- Always divide into whole risers — every rise must be identical. One odd step, top or bottom, is a classic trip hazard
- Watch the headroom — a shallow stair starts further into the room and so conflicts sooner with the edge of the floor above
- Stair cladding kits — overlaying existing treads barely changes the rise but takes a few millimetres off the going. Check that you still comply
Related terms
- Going
- Walking line
- Landing
- Overhang
Want to learn more about construction terms? Visit our knowledge base at fredsdiyplans.com.