Spiral Staircases in Nairobi: Where They Work and Where They Do Not

Spirals save floor area and cost you in every other way

A spiral is the right answer when floor space is the binding constraint and nothing else is: a roof access, a mezzanine office, a compact loft, a second stair to a servants’ quarter.

It is the wrong answer as a main household stair, and clients are often surprised by how strongly we say that. Furniture cannot go up one. Two people cannot pass. Carrying anything bulky is awkward and carrying anything heavy is unsafe. And the narrow inner end of every tread is where people misjudge their footing.

Diameter decides everything

• Under 1.4m, access only. Fine for a roof hatch, unpleasant for daily use.
• 1.4m to 1.6m, comfortable for regular single-person use.
• 1.6m and above: genuinely usable, and at that point a compact dog-leg stair often occupies a similar footprint while being far better to use.

That last point is the one worth pausing on. Clients arrive wanting a spiral to save space and frequently discover a small straight or quarter-turn flight fits after all.

Headroom is the constraint people miss

You need clear height above every tread as the stair winds, and the tightest point is usually where the flight passes beneath the floor opening it emerges from. On a retrofit into an existing slab opening, headroom rather than diameter is often what rules the design.

We measure the opening before quoting.

Construction

A central pole with radiating treads and a spine-fixed balustrade, or a stringer-supported spiral where the pole is undesirable. Treads in chequer plate, timber or glass.

Quoted per flight after measuring the opening and the floor-to-floor rise: there is no meaningful per-metre rate for a spiral.