Spanish Ramp Gradients: General Ramp vs Accessible Itinerary (CTE DB-SUA)

The requirement

Spain sets two ramp limits, not one. A general ramp is capped at 12% (CTE DB-SUA 1, §4.3.1.1). A ramp on an accessible itinerary is banded by flight length instead: 10% under 3 m, 8% under 6 m, 6% for anything longer (§4.3.1.1(a)).

Both rules sit in the same Documento Básico, DB-SUA. Which limit applies depends on where the ramp is and what it connects. And the CTE has its own trigger: any path sloped over 4% counts as a “rampa”.

DB-SUA 1: the general ramp. This branch covers any ramp that is not part of an accessible itinerary. Think a change of level inside, or most ramps around a normal house. The slope is capped at 12% (§4.3.1.1). A general ramp also needs:

A landing at the top and bottom of a same-direction run. It must be at least as wide as the ramp. And at least 1.50 m long on the line of travel (§4.3.2.3, §4.3.3).
A landing where the ramp turns must not reduce the ramp’s width.
A flight no longer than 15 m (§4.3.2.1).
A handrail at 90–110 cm, once the ramp rises more than 550 mm at a slope of 6% or steeper (§4.3.4).

DB-SUA 9: the accessible itinerary. This branch is stricter. A scoping rule decides who has to meet it. DB-SUA §1.1.1 says the accessible rules do not apply inside the private limits of a single-family dwelling. One route still must comply: the outside path from the dwelling to the public road. That path must be an accessible itinerary, unless the dwelling itself is exempt. So on a normal house, the front-door approach is usually where these bands bite. The gradient is banded by flight length:

Flight length	Max gradient
Under 3 m	10%
Under 6 m	8%
6 m or longer	6%

(§4.3.1.1(a).) An accessible ramp also needs:

Cross-fall (pendiente transversal) of 2% max (§4.3.1.2).
Clear width of at least 1.20 m (§4.3.2.3).
A flight no longer than 9 m (§4.3.2.1).
Extra handrails once the ramp rises more than 18.5 cm at 6% or steeper (§4.3.4). You then need continuous rails on both sides. Add a kerb of at least 10 cm on any open edge. And fit a second, lower handrail at 65–75 cm.

CTE DB-SUA 1 · rampa general

Which one applies? Building the approach to the front door of a normal single dwelling house? That outside route usually has to hit the DB-SUA 9 length bands. A general ramp elsewhere on the job gets the flatter 12% test instead. That covers ramps inside the house, into a shed, or a change of level in the garden. The two tests can give different answers for the same rise. Don’t assume they match.

Vehicle ramps are a separate case again. A car-park ramp that also carries people on foot, and is not on an accessible itinerary, is capped at 16% (§4.3.1.1(b)). It has no fixed limit on flight length.

Headroom uses the same rule as a stair. You need at least 2.10 m in restricted-use zones, and 2.20 m everywhere else. That figure sits in DB-SUA 2 §1.1, not in the ramp rules.

Work it out on site

You are building the accessible route to a new dwelling’s front door. The threshold sits 450 mm above the path. How long does the ramp need to be?

Try 10% first. The steeper bands only cover short flights, so check them first. The 10% band only covers flights under 3 m. At 10%, a 450 mm rise needs 450 ÷ 0.10 = 4500 mm (4.5 m) of run. That is over the 3 m limit, so 10% is out.
Try 8%. This band covers flights under 6 m. 450 ÷ 0.08 = 5625 mm (5.625 m). That fits under the 6 m limit, so 8% works.
Add the landing. At least 1.50 m long, at the top.

So: about 5.6 m of ramp at 8%, plus a 1.50 m landing. You could also drop to the 6% band. It covers flights of 6 m or longer, with no length cap of its own. The slope calculator does the rise-over-run and band check for you.

Do it in 5 seconds

Part of the Spanish Building Regulations hub. The DBs that set the rules all live there.
Building the stairs that ramp might replace? See Spanish stair & barrier rules.

Sources

CTE DB-SUA — Seguridad de Utilización y Accesibilidad, §4.3.1.1 (general ramp gradient, accessible-itinerary bands, vehicle ramps), §4.3.1.2 (cross-fall), §4.3.2.1 (flight length), §4.3.2.3 / §4.3.3 (landings and width), §4.3.4 (handrails), and §1.1.1 (accessibility conditions not mandatory inside the private limits of a single-family dwelling, except the exterior itinerary to the public road). Read it at 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 before you build to it.

Frequently asked questions

What ramp gradient does the CTE allow?

There are two limits. A general ramp, one not on an accessible itinerary, is capped at 12% (DB-SUA 1, §4.3.1.1). A ramp on an accessible itinerary is banded by flight length instead: 10% under 3 m, 8% under 6 m, and 6% for anything longer (§4.3.1.1(a)).

Does my ordinary house have to meet the stricter accessible figures?

Not inside it. DB-SUA §1.1.1 says the accessible rules do not apply inside the private limits of a single-family dwelling. But the outside route from the dwelling to the public road still must comply, unless the dwelling is exempt. So the front-door approach is usually the part that must hit the length bands.

How long do landings need to be?

For a general ramp, a landing between same-direction flights must be at least as wide as the ramp. It must also be at least 1.50 m long on the line of travel (§4.3.2.3, §4.3.3). A landing where the ramp turns must not reduce its width. Accessible ramps also need a clear width of 1.20 m.

What handrail applies, and when is one required?

A handrail on one side, once the ramp rises more than 550 mm at a slope of 6% or steeper (§4.3.4). Height is 90–110 cm. On an accessible itinerary, a rise over 18.5 cm at 6% or steeper needs continuous handrails on both sides, a kerb of at least 10 cm on open edges, and a second, lower handrail at 65–75 cm.

What about a vehicle ramp into a garage?

A car-park ramp that also carries people on foot, and is not on an accessible itinerary, is capped at 16% (§4.3.1.1(b)). That is steeper than either pedestrian figure. It also has no fixed maximum flight length.