Drainage
SANS 10400-Part P, Drainage, Plumbing,
Main Picture Above: A new drainage and sewage containment tank installation.
Sanitation and Water Disposal

Drainage and plumbing is not only what you see above ground. All water, waste disposal, soils and stormwater have to be drained away and treated to maintain safety and health. In many instances these pipes cannot be seen as they are buried underground and have to be installed by a qualified plumber using the correct pipework.
How Many Toilets?
We get a number of requests asking us for the number of toilets, urinals, wash-hand basins and baths that have to be installed in buildings. This depends on how many people will live or work in a particular building. Part A20 states that:
“The occupancy of any building shall be classified and designated according to the appropriate occupancy class given in column 1 of table 1 and such classification shall reflect the primary function of such building: Provided that, in any building divided into two or more areas not having the same primary function, the occupancy of each such area shall be separately classified.”
Sanitary Fixtures Tables.
There are two tables below Table 5 for residential accommodation and Table 6 for personnel in the workplace these are extracted fron the SANS 10400 Part P – Drainage.
How to find a sewer line.
Sewer lines transport wastewater from your home to either the city’s main line or to a septic tank on your property. If you’re installing a new sink or toilet, you need to connect it to your home’s sewer line so fresh water doesn’t get contaminated. When you’re trying to find the sewer line on your property, contacting the city or a professional service is the easiest way. If you still need to find the sewer lines, feed the detector of a pipe locator into a drain and use the wand to find it in your pipes. As soon as you know where your sewer line is, you can start working!
More on Drainage and Plumbing
The need for proper drainage and plumbing is essential to the health and safety of your home. Without proper drainage, water can accumulate and cause damage to your structure and foundation. It can also lead to the growth of mould and mildew, which can be hazardous to your health.
Plumbing is also important to ensure the safe and efficient functioning of your home’s water system. Without it, your water supply can be contaminated and your home can become unsafe. Proper drainage and plumbing are necessary to keep your home safe and healthy.
More specifically, proper drainage and plumbing help to prevent flooding, reduce potential water damage, and keep your home’s water system running efficiently. Additionally, they help to maintain the quality of your home’s water supply, which is essential to your health. Finally, they can help to reduce the cost of repairs and maintenance, as they can help to prevent costly problems before they occur.
Drainage is a very important factor in maintaining sanitary health. Proper drainage can help reduce the spread of disease by providing a suitable environment for proper waste disposal and preventing the spread of water-borne illnesses. Proper drainage can also help reduce flooding, reduce the risk of groundwater contamination, and improve the overall quality of the local environment.
Drainage systems should be designed to ensure adequate and appropriate drainage of wastewater, stormwater, and other runoff, while also considering the local climate and topography. More specifically, proper drainage can help reduce the risk of contamination from septic tanks, sewage, and other sources of waste by ensuring that wastewater is properly disposed of in an appropriate manner. Additionally, proper draining water can help to prevent flooding and reduce the risk of groundwater contamination.
READ MORE HERE: Sewer line …
Non-Water-Borne Sanitary Disposal
Occupancy/building classification is covered in SANS 10400, Part A: General Principles and Requirements. It doesn’t specify offices as such, but I assume your block would fit into category B3: “Low risk commercial service
Occupancy where a non-industrial process is carried out and where neither the material handled nor the process carried out falls into the high or moderate risk category.” Floor space is only relevant to how many people may work in such a space, viz. ”1 person per 15 m2″.
The provision of sanitary fixtures is covered in Part P: Drainage, and is based on the population for which the building is designed.
Where “separate sanitary facilities are provided for each sex, the number of sanitary fixtures installed for them shall be based on the population of that particular sex for which such facilities are intended and, if the number of persons of each sex cannot be determined, it shall be assumed that they are in equal proportions”.
“Where fixtures are to be situated in separate groups, the number of fixtures in any group shall be based on the calculation of that portion of the total population for which the group is intended”.
If there are less than 15 people working in the office space, you must have at least one toilet pan, one urinal and one wash-hand basin if they are all men; and two toilets and a basin if they are all women women. The toilet facilities required increase according to the number of people “populating” the building. Technically you could have well over a hundred people working in that space, in which case you will need three toilets, six urinals and five basins if they were all men; and nine toilets and five basins if they were all women. And there are figures in-between for less than 30, 60 and 90 people. You would need to work out ratios from these figures.
If members of the public are able to access the toilet facilities, you don’t need more – but if they cannot access them, you’ll need an additional toilet and basin for visitors.
Good morning
I run an office block and would like to know the ratio of number of toilet cubicles per person – floor space is 2667m2
Thank you
Michele
Do I understand this? You have a gutter that runs across a building that forms two garages – yours and your neighbors, and they are preventing the flow of water through the gutter? If this is the case NO THEY ARE NOT permitted to do so.
Good day,
We have a common building garage with a the neighbours. We always had the same gutters and there was no block between in the gutters between the garages. No the neighbours had changed their gutters, but they put a block between in the gutters between the two garages. My question is can they do it?
Regards
Petra
The rules and regulations as they apply to plumbing are extremely strict. I do have SANS that I can look at (starting with the NBR Part P: Drainage), and will get back to you asap. Perhaps I will write a blog post and include some of the drawings to show how the guttering etc should be done. I can tell you one thing though, if the water is draining into the building the drainage has not been done correctly and is therefore illegal!
I live in a sectional title complex and we have an issue with the drainage of rain water off the roofs and into the gutters to be drained away via the downpipes (when they are not blocked by leaves and/or bird droppings). The problem I see is that the gutter has been placed directly on the outside wall and does not hang from the roof away from the wall. The back upright bit (the bit under the edge of the last tile) of the gutter trough is lower than the front bit facing the property. When a heavy downpour occurs and there is a blockage in the side downpipes, the water has no other option but to run over the back bit under the tile and then into the house and onto the ceilings inside. It seems the gutters are installed the wrong way round.
I’d like to know if there is an official building standard available that I can show the trustees, who are dragging their heels and hesitant to repair this and finding excuses why not to repair it.
Just this last December I incurred severe losses in my personal possessions due to water damage that could have been avoided had the gutter issue been sorted out many years ago. This debate in the complex has gone on for years now, without remedy.
Any help would really be appreciated.
YOu do have a responsibility to drain the water away from the building – and not onto someone else’s property. My first thought is that perhaps digging a soakaway on the common land would help to alleviate the problem. I have no idea what type of soil you have, but for example if it is clay, then it won’t drain easily. Alternatively you may have to build a drain that will channel the water to a municipal stormwater drain.
If you believe that your neighbour had a problem prior to construction of your garage, you need to ascertain where THAT water was coming from.
We have just built a garage on the side of the house (all permit and permission has been granted by the Municipality and the Body Corporat) The unit is a cluster hom. We have a down pipe put in at the side of the garage to drain the excess wast away. The water goes onto common property.which is a pan handle to two other units. They are complaining that we are flooding their property, which never happend before the garages was built. (Which I know for a fact they did have a problem) Could you please advise what we can do to elevate this problem for all concerned.
Hester that it totally illegal. I suggest that you contact the health inspector for the Parys municipality and report the establishment immediately. You will probably find that the building work they have undertaken is illegal too. Furthermore, there are laws that govern buildings that cater for visitors, as well as local authority by-laws that require lodges etc to have a permit to operate. You might also call one of the local newspapers in Parys and tell them about your experience.
Hello.
My husband and I went to Parys in the freestate for a breakaway weekend, what was meant to be an enjoyable weekand was soon destroyed by the stench of urine and feaces in the room we booked at the river bush lodge parys which was very clearly just an old house which they rhinowalled into seperate rooms. We soon dicovered that the drain pipe for the washbasin is connected to the drainage pipe for the toilet. Is this in anyway according to any south african building code?
Thank you
Thanks
There aren’t any regulations that require you to lay paving. The regulations relate to adequate drainage rather than specifically gutters, paving or anything else. Generally though you will need gutters to channel rainwater from the roof. Sometimes architects design other ways – e.g. using hi-tech chains – but these aren’t common and need to be correctly designed.
Are there regulations regarding either having gutters on a house or the minimum width of paving around a house?
Are you trying to answer some sort of test? The questions are not specific enough. e.g. Rainfall runoff method for what/where? Return period for what? Minimum pipe diameter for what?
Are you saying that the overflow from your toilet flows into your shower? If so it sounds as if your plumbing installation is illegal. Ask other tenants in the building if they have the same problem, and call in a registered plumber for a quotation to rectify the situation. Once you have this, contact your landlord and demand that the fault is fixed. If you still have problems, you might want to contact the Plumbing Association of SA for further advice.
Contact the Plumbing Association for assistance. They will be able to tell you EXACTLY what should have been done. I do know that if an extra bathroom was added, plans would definitely have been required. Please let me know what happens either way.
Hi Penny
I have neighbours in the unit above mine, who have added on an extra bathroom. The new single stack 110mm pipe runs down the wall and connects to the main existing sewer via a manhole, situated at least 10 meter away, outside my kitchen, but on land belonging to the Body Corporate. The neighbour has completed this alteration without submitting any building plans to the local authorities, or the Body Corp. for approval and is contending that no building plans are needed. This problem has been compounded by a building inspector who has agreed that the national building regulations have not been violated. I believe it is necessary to obtain permissions prior to building These plans, I believe, need to be lodged and approval granted in writing, which would become a permanent record for all present and future owners. My question is: Are plans needed to be submitted to the local council for approval for this alteration from a drainage perspective?
Many thanks
Lindsay
Good day. I am currently renting a flat where I have found that all my drainage is flowing into the same line, as result if the drain bloks up the over flow goes directly into my shower. At previous residanses this was not the case. There was atleast a split in the line like an open drain witch seperated my water from he sinks and shower from the tiolet. I would like to know if this is according to standard or not
Hello,
I’m looking for some info on South african building regualtions would you be able to answer some questions for me?
1. what rainfall runoff method is reccommended to use?
2. what return period do the regulations reccommend that you design for?
3. is there a minimum pipe diameter that can be specified?
4. What is the minimum velocity reccommended a self cleaning flow?
5. what is the minimum distance between access chambers?
Thanks
Wendy there is no one type of pipe or size pipe that is suitable for water drainage. But all plumbing jobs MUST be undertaken by a qualified and registered plumber who will know which is the best for your job. The SANS are lengthy and there are several of them. If you want to wade through them yourself you can go to your nearest SABS library and ask them to give you anything that relates to water drainage.
Dear Penny,
Could you kindly advise what type of pipe and size is the SABS approved for water drainage? This would be for our upstairs shower. Where could I possibly find this information?
Many thanks
Wendy
Barry the building regulations and other SANS (of which there are several) that relate to plumbing are VERY strict. If your home is being flooded as a result of bad drainage, I am sure that you have a claim of some sort. The question is against whom. And as you say, whose responsibility is it to manage the flooding. You say you have bought in “an estate”, but it isn’t clear what sort. e.g. Do you have a body corporate? Also did you buy a new home?
I would start with your local authority. Query the drainage issues with them first. And/or, contact the Plumbing Institute of SA, IOPSA. You will their contact details on their website: http://www.iopsa.org.za/
I do know that IOPSA has tables that indicate how much rain different sized gutters can channel off roofs when a certain quantity or rain falls per hour. This is intended to assist plumbers fit the current outlets etc. They will also be able to tie you info about the specs for drainage pipe.
Please let me know what happens. Good luck.
To Whom it May concern
I am seeking information regrding unit standars or guidelines for stormwater drainage, my problem is as follows, I live on an estate with over 250 Units, 55 of these units have a single 110mm PVC pipe running through the back of there properties for the drainage of storm water, these are fed from the gutters of each home. Surely this is insufficient, the reason why I am upset is when it rains my property floods as I am the second last house of the 55 houses thus I am at the bottom of the hill, I bought one year ago and have had 3 floods which have destroyed my garden and blown a pool pump. Where can I get help and information so I can have clarity on who’s responsibility it is to manage the flooding!
You are not permitted to start building before plans have been passed by your local council. They will then inspect at various times, the first being once you have dug your foundations. All plumbing would need to be signed off by a registered plumber.
HI There, I am currently builing a laundry room in my yard and I plan to have plumbing for the washing machine and sink. Please can you kindly tell me if I need to have this inspected by the council?
many thanks
Sam