Steps and stairs

All diagrams taken from Designing for Accessibility, 2004 Edition, copyright CAE/RIBA Publishing)

Steps and stairs should be carefully detailed for the benefit and safety of everyone. Accompanying handrails are important for people with walking difficulties and impaired balance. Blind and visually impaired people benefit particularly from handrails which extend at the top and bottom of flights, a tactile surface to indicate the top of a flight of stairs, clearly distinguished nosings and a going which suits a natural cadence, especially when descending. Recommended nosing profiles assist people with leg braces or prosthetic devices who would have difficulty with sharp projections or abrupt angles. Solid risers also assist those who need to use canes or crutches on the step above to help maintain their balance.

Building Regulations

In England and Wales, building design and construction is governed by the Building Regulations. These regulations comprise a series of requirements for specific purposes: health and safety, energy conservation, prevention of contamination of water and the welfare and convenience of persons in or about buildings.

Part M of the Regulations sets minimum legal standards for access and use of buildings by all building users, including disabled people. Since a requirement for access was first introduced in 1985, there have been a number of changes to and extensions in the scope of access regulations.

The regulation avoids specific reference to, and a definition of, disabled people. This inclusive approach means that buildings and their facilities should be accessible and usable by all people who use buildings - including parents with children, older people and disabled people.

Previously, Part M covered new buildings and extensions to existing buildings. The 2004 revision brings Part M into line with other parts of the Building Regulations by extending its scope to include alterations to existing buildings and certain changes of use.

Approved Document M

Building Regulations are supported by 'Approved Documents' which give practical guidance with respect to the regulations. While their use is not mandatory - and the requirements of regulations can be met in other ways – Approved Documents are used as a benchmark by the local authority. The new Approved Document M (AD M), published in November 2003, offers technical guidance on providing access to and within buildings. It is informed by the relevant British Standard (BS 8300:2001 (Incorporating Amendment No.1) Design of buildings and their approaches to meet the needs of disabled people – Code of practice), although the British Standard also contains guidance on issues that are not appropriate or realistic to control under Building Regulations approval and inspection procedures, such as interior decoration and the selection of door ironmongery. Dimensional criteria in the new AD M are largely in accordance with BS 8300:2001. Where there are differences, these result from accumulated experience fed back to the Government during its consultation on the new AD M, and this should be followed in preference to dimensional criteria in BS 8300:2001.

It is important that reference is made to AD M for details of the circumstances in which Part M applies and what provision is required.

Disability Discrimination Act 1995

From 1 October 2004, under Part 3 of the Disability Discrimination Act 1995 (DDA), service providers have a duty to make reasonable adjustments to overcome physical barriers to access. For further information on the DDA visit the Disability Rights Commission website www.drc.gov.uk

Planning permission

Approval may be necessary for adapting steps or stairs at the front of a building. Particularly if the building is listed or in a conservation area any proposed design will also need to be in character with the building, which may impose additional constraints, particularly where space is limited. English Heritage guidelines Easy Access to Historic Buildings features case studies of access improvements in conservation areas and listed buildings.

Design guidance

External steps

Steps should always be provided as an alternative to ramps steeper than 1:20, as they are preferred by some ambulant disabled people. Safety is an important consideration when designing and detailing flights of steps.

For dimensions see Figure 1. below

Figure 1 External stair dimensions

Lighting can be located at the side of the flight, should be consistent along the full flight and adjoining landings, and should not cause anyone to negotiate the stairs in their own shadow.

Straight flights are easier to negotiate than curved or dogleg flights.

The unobstructed width of flights should be at least 1200mm.

Handrails should be provided, however short the flight (see Figure 1 and section on handrails below).

On wide flights of steps, handrails should be used to divide the flight into channels. AD M states that on flights of steps wider than 1800mm, handrails should be used to divide the flight into channels between 1000 and 1800mm, (but note anomaly here: taking into account the width of handrails, a flight needs to be at least 2050mm wide to be divided such that each channel is 1000mm wide).

Level landings at least 1200mm long should be provided at the top and bottom of the flight of stairs, free of door swing across the landing (see Figure 1).

Surfaces should be slip-resistant. A 'corduroy' hazard warning surface of raised ribs set parallel to the step nosings should be provided at the top and bottom of each flight as a warning to people with sight impairments of the presence of a tripping hazard (see Figure 2).

Figure 2 Corduroy tactile surface detail

• Corduroy surfaces should also be used at intermediate landings where there is access onto the landing other than from the steps themselves or on large intermediate landings where the handrails are not continuous.
• Nosings should be integral with the step and distinguishable in colour and tone (see Figure 3).

Figure 3 Nosings

• Nosings should be used on the front face as well as on the top of each step so that they are visible when ascending and descending.
• A flight between landings should not contain more than 12 risers if the going is less than 350mm or 18 risers if the going is 350mm or more.The rise and going of each step should be consistent in a flight, between 150 and 170mm (with possible exceptions where adjacent to an existing building the riser may be greater than 170mm).
• Open risers should not be used. Spiral stairs, tapered treads and tapered risers are not recommended, as they are exceptionally difficult for many people.

Avoid isolated single steps.

Figure 4 Step profiles and number of risers

Handrails

• People who have difficulty negotiating changes of level need the support of handrails. They should be provided in conjunction with changes in level, flights of ramps and steps.
• For heights of handrails see Figure 1.
• Handrails should be continuous across flights and landings.
• Consideration should be given to the provision of a second (lower) handrail set at 600mm on stairs, particularly in schools, for use by children and people of short stature.
• For handrail profiles and dimensions see Figure 5.
• Handrails should be easy to grip and provide good forearm support for people who are unable to grip. They should be configured with a positive end to reduce the risk of clothing being caught on the ends of rails.
• Surfaces such as hardwood or nyloncoated steel are recommended in preference to surface materials that are cold to the touch.
• The handrail should be easily distinguishable from its background, without being highly reflective.

Figure 5 Handrail profiles