Handrails and Balustrades Regulations: Question Time

As a specialist supplier and installer of handrails and balustrades systems there are a number of questions we get asked on a regular basis, in this newsletter we aim to answer them and hopefully make your next specification an easier task.

1. Can we specify horizontal bars or wires?
Building Regulations Approved Document K (ADK) states: In a building that may be used by children under five years of age, construct the guarding to a flight of stairs to do both of the following.

  • Prevent children being held fast by the guarding: ensure that a 100mm sphere cannot pass through any openings in the guarding
  • Prevent children from readily being able to climb the guarding.

In our experience this means the only places really suitable for horizontal bars and wires are office and factory buildings where it is certain children under the age of 5 are unlikely to be present.

2. Some types of guarding leave a triangular void between the bottom of the balustrades and the riser/tread. Is this acceptable?
This void is usually the result of a tread fixed balustrades with a solid infill panel such as glass and will almost always allow for a 100mm sphere to pass through which under ADK is not permitted.

The Approved Document does not give guidance for this type of guarding. Subject to the approval of the building control body, this type of guarding will usually be acceptable in buildings other than dwellings, providing the bottom of the guarding is not more than 50 mm above the pitch line (measured perpendicular to the pitch line).

If you are still concerned about this void there are a number of ways to eradicate it including fixing the balustrades to the string of the stair and dropping the bottom of the guarding panel below the pitch line or specifying a stair with a solid continuous stringer (usually timber or steel).

3. Approved Document M also gives guidance on stair and ramp design. Where there appears to be a conflict between the guidance in Approved Document K and Approved Document M which takes precedence?

The guidance in Approved Document M deals with ensuring ease of access to and around buildings, which is different to the minimum standards necessary to secure the safety of people using stair and ramp design.

So this is a difficult question to answer and will depend on a number of factors regarding the use a building control professional may need to ask relevant questions, such as:-

  • Is one stair self-evidently the principal circulation stair or are all the stairs given equal prominence in the design?
  • If the former, are the secondary stairs for escape only?
  • If the latter, might an ambulant disabled person reasonably expect to use any of the available alternatives, or, to put it another way, might it be unreasonable to expect such a person to traverse whatever distance would be required to reach a sole accessible stair?
  • If secondary stairs are for escape only, is there adequate provision for assistance for disabled people?
  • Does the mean of escape strategy involve the use of evacuation lifts?

Depending on the answers to these sorts of questions, it might be concluded that it would be reasonable for a principle stair in an accessible location to be designed in accordance with AD M while a secondary stair designed primarily for escape may be satisfactory if designed in accordance with AD K.

How is the visual contrast between a handrails and it’s background measured?
Light reflectance value (LRV) is the total quantity of visible light reflected by a surface at all wavelengths and directions when illuminated by a light source.

The LRV scale runs from 0, which is a perfectly absorbing surface that could be assumed to be totally black, up to 100, which is a perfectly reflective surface that could be considered to be the perfect white. Because of practical influences in any application, black is always greater than 0 and white never equals 100.

Contrast should be 30 points difference on the LRV scale.

Can stainless steel handrails be specified externally?
Doc M, K and BS8300 all state that handrails in locations subject to extremely cold or hot temperatures should not become excessively hot or cold to touch. This usually means external applications however consideration should be given to handrails in unheated buildings such as multi storey car parks.

In these instances our recommendation would be to specify a nylon sleeved system such as the Nylon Line, timber can also be used but requires more maintenance and would not prove to be as vandal resistant. The regulations also state that “in areas where resistance to vandalism or low maintenance are key factors, use of metals with relatively low thermal conductivity may be appropriate“In these situations stainless steel may also be considered.