PART K · Falling collision and impact
Staircase building regulations explained
A staircase must be suitable for the building and safe to use. Part K provides guidance on its geometry and protection, while fire safety and accessibility can introduce additional considerations. There is no single staircase detail that suits every type of building.
Which dimensions matter
The design should show rise, going, pitch, headroom, width where relevant, landings and handrails or guarding. The applicable guidance distinguishes different stair types and uses.
Do not select just one figure, such as the pitch, and assume the rest of the design is acceptable. The dimensions work together.
Why are finished levels important
Floor finishes change the final level. If a stair is ordered from rough structural measurements, the first or last step may differ from the intended arrangement.
Measure and coordinate the completed levels before manufacture. Include the expected floor build-up at both ends of the stair.
Are loft stairs different
Loft conversions can involve limited space and specific guidance on headroom or alternative arrangements. Those provisions have conditions. They should not be treated as general permission for a steep stair or restricted escape route.
Ask the designer to explain the route used and how the staircase connects to the existing house's fire safety arrangement.
What about turning stairs
Winders and changes of direction need proper detailing. Landings, doors opening near the stairs and the position of handrails also affect safe use.
For example, a door should not be added to a carefully designed landing without reviewing its effect on movement and available space.
What should you obtain before ordering
Get dimensioned drawings based on the actual building, with the relevant design assumptions recorded. Confirm who checks the manufacturer's details and any site changes.
At completion, check the installed stair against the agreed design, including guarding and handrails. A stair that fits the opening is not necessarily one that meets the applicable requirements.