# Spanish Stair & Barrier Rules: Riser, Going, Handrails, Guarding

The CTE DB-SUA 1 numbers for a private dwelling stair (uso restringido) — 20 cm max riser, 22 cm min going, 90–110 cm handrail — with no 2C+H comfort formula for a house's own stair.

- Canonical HTML: https://www.chippy.tools/building-codes/es/stairs/stair-and-barrier-requirements/
- Publisher: Chippy Tools
- Updated: 2026-09-06
- Market: es
- Code edition / reference: CTE DB-SUA (RD 450/2022)
- References: ES CTE DB-SUA 1


## The requirement

A house stair in Spain is built to **DB-SUA 1**, §4.1. Riser (contrahuella): **20 cm** max. Going (huella): **22 cm** min. Clear width: 0.80 m min. The handrail-height range discussed below belongs to general-use stairs, not an independently confirmed private-stair limit. Guards: 0.90 m, or 1.10 m past a 6 m drop. There is no 2C+H check for a home’s own stair.

DB-SUA is the CTE’s book on safe use and access. First, get the class right. The CTE glossary (Anejo A) puts the stair inside a single-family or attached home in the class **uso restringido**. That means restricted use. Shared and public stairs sit in “uso general” instead. That class has stricter rules, and one extra rule. This page covers the house class.

- **Riser (contrahuella):** how tall each step is.
- **Going (huella):** how deep each step is, measured in the direction of travel.

For this class, each riser can be **20 cm** tall at most. Each going must be at least **22 cm** (DB-SUA 1, §4.1). Keep every step in a flight the same. The same clause sets a clear width of at least **0.80 m** per flight (§4.1, point 1).

Curved stair? Under 1 m wide, measure the going on the stair’s own axis. At 1 m or wider, measure 50 cm in from the narrow side. Even then, the going must not drop under 5 cm at the narrow end. And it must not pass 44 cm at the wide end.

**No 2C+H check for a house stair.** DB-SUA 1 does carry a comfort formula. It keeps twice the riser (C) plus the going (H) between 54 cm and 70 cm. But §4.2.1 states it only for uso general stairs, the shared or public class. A home’s own stair skips it. The riser and going limits above are the whole rule.

**Diagram labels:** ≤ 20 cm; ≥ 22 cm

CTE DB-SUA 1 · uso restringido

**Headroom** has its own rule, in **DB-SUA 2**, §1.1. That is the impact section, not SUA 1. You need 2.10 m clear in restricted-use circulation zones. That means a home’s halls and landings. Other circulation zones need 2.20 m. A door threshold needs 2.00 m. The Ministry’s own note backs this up: the 2.10 m figure covers circulation zones only. It does not cover a living or sleeping room. So a sloped ceiling over a stair does not fail just because the room runs low somewhere else.

## Handrail & guarding

The **handrail (pasamanos)** sits **90–110 cm** above the pitch line. Read this one with care. The 90–110 cm figure sits in §4.2.4, the uso general clause. The house-stair clause (§4.1, point 4) requires a barrier on any open side. It gives no height of its own. This page has not verified a cross-reference applying that height range to the house class. Do not read it as a confirmed private-stair limit.

Guarding (barreras de protección) protects a drop. DB-SUA 1 uses one rule for every kind of edge. Stair, landing, floor or balcony — the rule looks only at how far the drop is, not at what kind of edge it is (§3.2.1).

| Drop protected                         | Guard height                   |
|----------------------------------------|--------------------------------|
| Up to **6 m**                          | **0.90 m** minimum             |
| Over **6 m**                           | **1.10 m** minimum             |
| Stairwell void narrower than **40 cm** | **0.90 m**, regardless of drop |

The gaps in the guarding matter too:

- No opening may let a **10 cm** ball through. That figure covers homes, school zones, and public zones used for shops or assembly. Other public zones: **15 cm**.
- A tread, a riser and a baluster’s lower edge can form a small triangle gap. That gap is exempt only if it sits **5 cm** or less from the stair’s pitch line (§3.2.3).

## Work it out on site

Say your floor-to-floor height is **2.80 m**. You are setting out a house stair.

1. **Pick the riser count.** 2.80 m ÷ 0.20 m (the tallest a riser can be) = 14. That is a clean number. So: **14 risers**, each **200 mm**, right at the 20 cm cap.
2. **Set the going.** Try 220 mm, the minimum. Fourteen risers means 13 goings. So the stair runs 13 × 220 = 2860 mm along the floor. Check it fits the space. Spain sets no 2C+H check for this class. So a deeper going is a comfort call, your call, not a code one.
3. **Check headroom and guards on their own.** Confirm 2.10 m clear above the stair. Guard any open side to 0.90 m, or 1.10 m past a 6 m drop.

Use the calculator to compare geometry for your chosen riser count. Check the applicable rise, going and other code limits separately.

## Do it in 5 seconds

## Related

- [**Spanish Building Regulations hub**](https://www.chippy.tools/building-codes/es/): how the one national CTE and its Documentos Básicos work.
- [**Irish stair & barrier rules**](https://www.chippy.tools/building-codes/ie/stairs/stair-and-barrier-requirements/): handy if you compare riser and going rules across countries.

## Sources

- **CTE DB-SUA — Seguridad de Utilización y Accesibilidad**, §4.1 (riser, going, restricted-use classification), §4.2.1 (2C+H formula, uso general only), §4.2.4 (handrail height, uso general), §3.2.1 (guard heights), §3.2.3 (guard-opening sphere rule), and DB-SUA 2 §1.1 (headroom). Read it at [codigotecnico.org](https://www.codigotecnico.org/).

**Read this first.** These figures are from the current **DB-SUA** articulado (Real Decreto 450/2022, de 14 de junio, corrected BOE 02/02/2023). A further partial revision of the CTE affecting DB-SUA was in public consultation at the time these figures were checked (not yet adopted) — always confirm the current DB-SUA text at [codigotecnico.org](https://www.codigotecnico.org/) before you build to it.


This page is general information for tradespeople and is not compliance, engineering or legal advice. Requirements are subject to state and territory variations and adoption timing. Always confirm requirements with your building certifier and relevant state authority.


## Frequently asked questions

### What class of stair applies to a normal house?

The stair inside a single-family or attached home is classed 'uso restringido' — restricted use. The CTE glossary (Anejo A) sets that class, and it is the class this page covers. Shared or public stairs are 'uso general' instead, a stricter, table-driven class with a different set of numbers.

### What is the maximum riser and minimum going for a dwelling stair?

Riser (contrahuella): 20 cm max. Going (huella): 22 cm min, measured in the direction of travel (DB-SUA 1, §4.1). On a curved stair under 1 m wide, measure on the axis. At 1 m or wider, measure 50 cm from the narrow side; going at least 5 cm at the narrow end, at most 44 cm at the wide end.

### Does the 2C+H comfort formula apply?

No, not to a home's own stair. DB-SUA 1 does carry the formula (54 cm ≤ 2C+H ≤ 70 cm; C is the contrahuella/riser, H the huella/going). But §4.2.1 states it only for 'escaleras de uso general' — shared or public stairs. A restricted-use house stair only meets the riser and going limits.

### How much headroom does a Spanish stair need?

2.10 m minimum in restricted-use circulation zones — a home's halls and landings. Other circulation zones need 2.20 m. A door threshold needs 2.00 m. The rule is DB-SUA 2 §1.1, the impact-risk section, not SUA 1. The Ministry's guidance confirms it covers circulation zones, not living or sleeping rooms.

### What handrail and guard heights apply?

Handrail (pasamanos): 90–110 cm. That figure sits in §4.2.4, the uso general clause. §4.1 requires a barrier on open sides. This page has not verified a cross-reference applying the 90–110 cm handrail range to private stairs. Guards: 0.90 m up to a 6 m drop, 1.10 m past it, any edge type (§3.2.1). Voids under 40 cm: 0.90 m.