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As a provider of premium commercial washrooms, one of the most frequently asked questions we get is, "How small can I make a superloo?"
There are many superloo dimensions to consider including the floor space, the type of sanitary fixtures, the fitting arrangement, the activity space, the circulation space, etc.
Architects strive to maximise their floor plate but before they can achieve that, they must consider the regulations in place specifying how many toilet cubicles should be installed. This figure depends on the density of people occupying the building and could affect the fitting arrangements which play a significant role in determining the size of a superloo.
As the trend grows to incorporate unisex washrooms, the Government is reviewing the current challenges and will take action to ensure better provision of toilets including specifying the number of toilets to be provided.
All the information provided in this article is based on Dolphin’s project experience with commercial washrooms in England combined with information found in BS 6465-2:2017 – The British Standards Institution (BSI) Publication on sanitary installations – Part 2: Space recommendations – Code of practice.
Minimum space arrangements for room layouts
The BS 6465-2:2017 provides guidance and recommendations for suitable dimensions when designing the minimum space arrangements. It is important to note that the figures presented in the BS 6465-2:2017 are intended for preliminary planning purposes showing typical minimum room sizes for various fitting arrangements, noting that different arrangements of the same fittings might result in larger spaces. It also recognises that fittings with different dimensions might require alternative size spaces.
Annex A (normative) of BS 6465-2:2017, addresses minimum space arrangements for room layouts, and you should refer to these dimensions to have a clearer idea of what to expect.
From experience, a typical superloo could be 1200mm wide and 1800mm long which is quite generous for a superloo layout, but some superloos come in at 1100mm wide. Regardless of how narrow you think you can make this cubicle, you still need to include the activity space for the main sanitary fixtures.
Choosing to go smaller than the average space is possible, however, before you make that decision you need to consider the details if you want to go below those measurements.
This is the area that allows a user to access the various sanitary facilities such as the WC pan, without adversely affecting access to other amenities such as the washbasin.
WC Pan activity space
The minimum dimension for a WC pan (back-to-wall or wall hung) must conform to 600mm depth in front of the toilet and 800mm wide. A minimum clearance space of 200mm should be provided between the side of the pan and any wall or fitting such as a toilet roll holder or soap dispenser. This allows the user to have adequate manoeuvring space when using the toilet.
Small washbasin activity space
Clear floor space must also be provided in front of a hand-rinse basin which conforms to 600mm depth in front of the basin and 800mm wide.
Activity spaces between the washbasin and the WC pan can overlap but both activity spaces should conform with their individual dimensions as set out in the BS 6465-2:2017.
Soap dispenser, waste disposal, and hand dryer
A soap dispenser, waste disposal, and hand dryer all have their own activity spaces. Fortunately, these fittings are not limiting factors in your design as they have a smaller activity space than that of a washbasin or WC pan and are likely to be superimposed.
Column of Clearance
A column of clearance is the adequate manouevering space provided so a user may easily access the cubicle and sanitary appliances. Essentially it is a turning circle giving the user a place to stand when the door opens and closes. It must be situated clear of the door swing and all fixtures and fittings, but the column of clearance is permitted to overlap the activity spaces of other fixtures. This radius should normally be a minimum of 450mm in diameter.
Although the door swing is permitted to overlap the activity space, it should not interfere with the column of clearance. Common dimensions for a door swing range between 760mm – 830mm whether opening inward or outward.
Generally, superloos have doors opening inward but you can also implement an outward opening door in your design to reduce the cubicle dimensions and the column of clearance would not be necessary. However, an outward opening door will require the necessary space provided in the passageway.
Pushing the cubicle size under the limit may negatively impact the layout when the door opens inwards. For example, if you have a washbasin or vanity unit on the adjacent wall from the WC pan and the cubicle dimensions are too small and cramped, this introduces the risk of the door hitting the edge of the vanity or washbasin when opened.
The thickness of dividing walls is a crucial element that can also determine the maximum amount of superloos installed in a washroom. Measurements need to be carefully planned to maximise the floor space without compromising the consistency of the cubicle dimensions. Failing to do so may result in unequal cubicle widths or losing out on an extra cubicle which may leave you below the level you require for your floor plate.
The thickness of wall dividers can be a result of making provision for the extensive pipework within the wall, therefore incorporating fittings such as a wall plate system for mounted taps can reduce the wall thickness by 20mm – 30mm.
For another example, a wall divider could include a wall cavity that has two water feeds and two power supplies from the taps facing opposite each other, each one belonging to the neighbouring superloo. The materials in their respective conduits are connected by a conduit adaptor which is used to divert the conduit horizontally or vertically. This allows the two parts to come closer together, thus reducing the size of the wall divider.
Answer some of these basic questions to determine how small you can expect to make your superloo:
- What is the size of the floor plate?
- How many superloos do you require?
- What is the proposed arrangement for all sanitary fixtures and fittings?
- How big are your fixtures and fittings?
- How many extra fittings do you require?
- Will the activity spaces overlap?
- Does the door open inward or outward?
- Are your design preferences being met?
- Are you prepared to remove certain design elements?
These are a few simple questions to get you started in the process, therefore, asking the questions “How small can you make it?”, or “What are the minimum superloo dimensions?”, will be answered with an overload of information that is packed full of detail. Dolphin Solutions can provide some ideas and assist you to achieve the superloo washroom you desire.
The ultimate question is: Are you willing to sacrifice quality and space to achieve the smallest superloo design possible?