What to remember: Toilets

A new version of BS 6464, which provides guidance for toilet provision, was published in March. This is a revised version of the 1994 standard. It is important in that it significantly changes the amount of provision required in many building types. The principle is to balance the provision to allow for more equal arrangements for men and women. However, there are several other significant changes that have far-reaching effects for the specifier.

The new standard

As a standard it identifies best practice, but it is not a legal obligation. Many are directly used in the Building Regulations approved guidance as a reference standard and, therefore, should be used by the specifier for clarification.

The current Building Regulation Part G 1992 references the 1984 version of the standard and is likely to be revised in late 2007 or early 2008.

Additionally statutory requirements for toilet provision in the workplace are found in the Workplace (Health and Welfare) Regulations 1992 that has the same provision as BS 6465 1994.

Although the new standard replaces the old one, which is withdrawn, it will still be current when referred to in other documents.

The Details

The changes relative to building types are:

• Dwellings. Provision simplified from 1994, dwellings on one level omitted. • Workplaces. Provision significantly increased.

• Shops. No longer based on area, but on the number of workers, which could be problematic with some designs.

• Petrol stations. Now included for the first time.

• Schools. Secondary school provision increased. Primary schools no change.

• Assembly and entertainment has been divided into two sub-categories:

(i) Where most use is during intervals.
(ii) Other use.

The provision is increased for both.

• Hotels, pubs. Slight increase.

• Clubs, bars and restaurants, swimming pools. No increase. What does this mean for specifiers?

Adoption of the new standard, particularly for offices, needs to be considered carefully by the specifier. A significant new principle is that calculations for the toilet provision should be based on those used for fire escape purposes rather than the frequently used British Council of Offices Best Practice Design guide, which bases toilet provision on a ratio of 60% male, 60% female of the design population density.

Basing toilet numbers on fire escape provision could present a problem, however, as this supposes a population density of one person per 6m2. Applying this figure to toilet provision, on top of the general provisions in the new standard (see “Example”), could potentially more than double the number of toilets required, which many would regard as excessive.

For cubicles containing hand basins and toilets (and where there are more than two) the provision according to the standard must be increased by a further 25%.

Provision of an accessible, or disabled, toilet can count as part of the overall WC provision for the building. This is a clarification of the 1994 standard and is logical to a point; presumably it would be added to the female numbers, although this is not clear.

An example for the provision of female toilets in a commercial office would be as follows (with a population requiring 10 WCs).

• The 1994 standard: 10 WCs.
• The BCO “60/60” rule (the 1994 standard plus 20%): 12 WCs.
• The 2006 standard @ 1 person per 10m²: 16 WCs.
• The 2006 standard @ 1 person per 6m²: 26 WCs.
• The 2006 standard @ 1 person per 6m² plus 25% if includes hand basin: 33 WCs.

What does this mean commercially?

While the Building Regulations continue to reference a previous level of provision, specifers can use the new standard. They should inform clients of the new standard and the implications. Clearly, there may be a commercial benefit to adopt some elements of the new standard, but implementing it to the full will result in a loss of lettable floor area, which will probably be unacceptable to the client.

Reducing the fire escape standard may also be considered to lessen the pro-rata toilet provision, but this also should not be recommended as it limits the future population of the building.