Public toilets are places where one is compelled to ease oneself in unfamiliar surroundings among strangers of the same sex. Therefore, the fundamental principles of the design of toilets include psychological studies and not just physical clearances and space requirement.
A number of different activity spaces are needed in a toilet: space occupied by the appliances itself, additional space required by the user and further space for their own belongings or circulation within the toilets. In many cases, these latter spaces may overlap on occasion. Common sense will dictate when this is appropriate and when it is not. Placing the appliances in order of use simplifies the circulation and reduces the distance travelled by the user. Using sensor-operated appliances should encourage hygiene.
It is difficult and costly to insulate the toilets acoustically and this problem can be resolved by planning isolation as much as possible. No unsupervised installation can prevent vandalism. Even with the most vandal-resistant appliances, an unsupervised facility will eventually become sub-standard. In most cases, facility engineers and cleaners play an important role, which will result in well-maintained toilets. However, all designs should allow for individual items to be replaced. Pipe work, traps and electrical supplies should be concealed for aesthetic and hygienic reasons.
Single entrance/exit plans work satisfactorily provided the path of the users do not cross each other and the entrance is wide enough. Dispensing with the entrance door to the public toilet not only helps improve ventilation within the toilet but also minimises hand contact for hygienic reasons. In many toilets, doors have been replaced by offset entrance maze which blocks the view yet allows easier, hands-free access. This approach eliminates the need for automatic doors, thus meeting stringent disability access guidelines.
Public toilets should be designed to minimise hand contact as far as possible for hygienic reasons. Electronic products for toilets such as flush valves and faucets require minimum maintenance but offer enhanced operations that promote sanitation and perceived cleanliness because of hands-free operation. There are several screening arrangements for installations showing the visibility from outside in each case. Consideration should be given to the positioning of the mirrors and to the gaps created by the hinges. For example, the access entrance to male public toilets should not open directly to the urinal area. Avoid entrances opening onto a wall surface with the mirror reflecting the urinals.
Directional signs leading to the toilets should meet the needs of the Handicap Welfare Association (HWA). The detailed requirements can be found in Building and Construction Authority’s (BCA) “Code for Barrier-Free Accessibility in Buildings”. Location of toilets should not be too remote from main traffic area to avoid long distance walking for the aged with weak knees. It has to be easily accessible for those with urgency and for better personal safety for the user. Further to this, signages used should be sufficient and prominently displayed in all main traffic passageways, so that the user does not need to ask for directions. Signages used should show contrast of dark solid figure against a white background and significant to be seen by the visually handicapped and the aged. Fancy signage using “Queen” and “King” or “Hat”, “High-heel shoes” are confusing and should not be encouraged. It is not easily distinguished by the visually handicapped and the aged.
The ratio of fittings in male and female toilets should be one WC & one urinal for male: two WCs for female.
As far as possible, fixtures such as urinals and WCs should be fitted back-to-back with common pipe ducts in between.
All public toilets should be mechanically ventilated. Small public toilets should be fitted with an exhaust fan as minimum.
A well-designed lighting system will save electrical energy and improve the appearance of the toilet. Poorly designed fixtures with discoloured diffusers go a long way to make a toilet dingy. Dark and shadowy, off-coloured lighting can create the impression that a toilet isn’t clean.
Natural lighting can be used to help create a softer, friendlier environment. Harsh lighting can create a cold and unwelcoming air while being inappropriate for the tasks being performed. It can also highlight hard-to-clean areas. Thoughtful selection of fixtures and lamps coupled with careful placement is essential.
All public toilets should be provided with warm-colour lighting for general lighting as well as down lights above the wash basin/mirror. The minimum general lighting level is 300 lux. Warm-colour lighting aids in creating a better ambience in the toilets, which in turn encourages more care and responsibility from the users.
Examples of good materials:
- Floor: Non-slip ceramic tiles, natural stone, homogeneous tiles, terrazzo
- Wall: Ceramic tiles, natural stone, homogeneous tiles, stainless steel, enamelled steel panels, glass block, aluminium panels, phenolic cladding.
- Ceiling: Mineral fibre board, fibrous plaster board, Aluminium panels or strips. Non-slip homogeneous tiles are often selected because they are durable and are relatively easy to clean. The walls should be tiled, allowing the cleaners to sponge down the walls and floors thoroughly with little difficulty. Another alternative is to use ceramic tiles or wall cladding.
Wall and floor tiles of large surface areas are encouraged for easy maintenance. The tile size should be at least 100mm by 200mm. Alternatively, any of the panels listed above could also be installed at the walls.
The most common type of ceiling finishes includes calcium silicate board and suspended ceiling tiles. If there is piping above the ceiling, for example, suspended tiles will permit easy access for maintenance and are more easily repaired in the event of spot damage. Calcium silicate board may be better suited for applications where access above the ceiling is not required. When the time comes for renewal of ceiling finishes, it is far less expensive to repaint calcium silicate board than to replace ceiling tile.
Use colours to brighten the toilet, create interest and produce a conducive environment. Colour, achieved with materials and lighting, is one of the vital ingredients in creating ambience. It can be part of the tile or stone finishes, or added to the applied finishes such as the enameling on steel or aluminium. If paint is to be used, it should be restricted to areas that are out of reach, e.g. ceilings.