Building components · Stairs & Level Change
Stair Riser
Explains the riser as a separate position from the tread — one a flight can be designed with or without — rather than as the back half of a step.
Educational reference entry. What this element has to do, and whether any particular arrangement of it is adequate, depends on the whole assembly, the loading, the exposure, local requirements, the manufacturer's instructions and qualified professional design.
Overview
What a stair riser is
A stair riser is the vertical face between consecutive treads. It closes the gap that would otherwise exist at the back of each step, so that a flight reads as a solid form rather than as a series of separated planes.
Whether it is present is a design decision, not a given. A closed-riser flight has one at every step; an open-riser flight has none, and the treads are carried without anything behind them. In some traditional timber flights the riser also does structural work, tying the treads together and stiffening the flight, which is why removing risers from an existing stair is not a cosmetic change.
Boundaries
How it differs from nearby elements
The distinctions that keep this entry from being a restatement of its neighbours.
- It is not a tread. The tread is the horizontal surface a foot lands on; the riser is the vertical face between two of them, and a flight can have treads without risers but never risers without treads.
- It is not a stringer. A stringer runs the length of the flight along its edge and carries the steps; a riser sits across the flight between two steps and carries little or nothing from the flight as a whole.
- It is not a stair soffit lining. The lining closes the underside of the whole flight as one raking plane; a riser closes the single gap between two steps and faces the room the stair is in, and a flight can have either without the other.
Terminology
Common names and aliases
These names describe the same element. The library keeps one entry per component so that a trade term or a regional name never becomes a second, thinner page.
- riser board
- step riser
- riser panel
Dependencies
What it depends on
What has to be right elsewhere for this element to do its job.
- Whether the flight is designed as closed-riser or open-riser, which decides whether the position exists at all.
- How it meets the tread above and the tread below, since those two junctions are what hold it in place and what is seen.
- Whether it is doing structural work in the flight, which differs between traditional and modern stair construction and is not visible once the stair is finished.
- What it is seen against, because the riser face is at eye level for anyone descending and at foot level for anyone ascending.
Considerations
Topics that genuinely apply here
Subjects worth discussing about this element. These are discussion topics, never measured values, ratings or performance claims.
The riser is fitted between two treads already set out, so it absorbs whatever inconsistency exists between them and shows it as a visible taper.
Risers take repeated contact from the toe of a shoe rather than from the sole, so damage concentrates near the bottom of the face rather than across it.
Removing risers from an existing closed flight to open it up changes how the flight is held together, which is a structural question rather than a finishing one.
A closed flight encloses the space beneath each step, and whether that closure is continuous affects how the stair sounds in use and what is heard beneath it.
Materials
Commonly formed from
Material families this element is commonly realised in. This states common practice only — it is not a statement that any of these materials suits this component in a particular building, which depends on the whole assembly and on qualified review.
Assemblies
Building systems this element is met in
The role this component fills inside each assembly. A role describes what the element does there — it is not a statement that this component suits that system in any particular building.
Clarifications
Commonly misunderstood
- That the riser is simply the decorative back of a step. In some flight constructions it ties treads together, and its removal alters the stiffness of the whole flight.
- That an open-riser flight is a flight with the risers taken out. The two are designed differently from the outset, and one cannot be converted into the other by removal alone.
Conversations
Questions for qualified professionals
Questions worth asking someone with the project in front of them. This page cannot answer them.
- Is this flight designed as closed-riser or open-riser, and does anything structural depend on the answer?
- How is each riser fixed to the treads above and below it?
- If risers are to be removed or added to an existing flight, what has been assessed about the effect on the flight?
- What is behind the risers, and is anything relying on that space being closed?
Go deeper
Related Build Design Hub guides
Planning guidance behind the decisions this element involves.
Preparation
Related planning checklists
Owner-side preparation before the conversation where this element comes up.
What this entry does not do
- This entry describes a position in a flight. It states no rise, thickness, opening size, guarding requirement or fire rating, and no dimension or performance value can be inferred from it.
- Whether an open-riser arrangement is permissible in a given building follows from local requirements and from who uses the stair; it is a design and compliance question rather than a reference one.
Stair & Level Change Elements
The positions that make up a stair and the elements that carry people safely between levels — treads, risers, the members beneath them, and the guarding at the edge.
Browse all stairs & level change entries →