Plumbing Aspects of House Construction

Plumbers generally present to you with a long list of items and only the shopkeeper can decode the list. But what if you are constructing your own house and don’t want to be taken for a ride. What do you do if your plumber mentions 20 MTA or 10 Elbows for a small work. So if you have not read the list of plumbing items you could read this article on “Plumbing list of items“. Now if you have the drawing you can derive how many elbows you need. How many MTA you need and so on. If you spend some more effort you can design a more effective layout for the pipes such that you save money and also ensure minimal bends so that you get high pressure in your shower area. You can do it, its very simple provided you know what he is trying to accomplish and what are the available options in terms of materials.

So lets get started by asking what happens during plumbing in your house construction time!

When is the first plumbing work required ?

Borewell pump and HDPE pipe are the starting point of plumbing. This work does not require any plumber to get things done. The work is normally a package from the person you buy the pump and pipe. He normally does the installation along with providing a external flexilbe pipe. This flexible pipe is your companion for the rest of the building where you do the curing work and spend your quiet evenings watering your dream project!
Plinth beam sewage pipe hole.

The next step is during plinth beam or foundation stones where you need to place a 6 inch pipe. This pipe is a placeholder for the drainage connection from your ground floor bathroom to the sewage pipe are where chamber needs to be constructed. Do not forget to place some cement bags or gunny bags inside the pipe so that concrete does not fill up into it. If you do not place this placeholder pipe you will need to later drill a hole or break open a hole for ground floor sewage connection!

See figure for more clarity.

[Note that the entire external sewage connection pipe is normally towards one side of your house if planned well]
All floors walls are completed and yet to be plastered

Now its time for internal plumbing work. Kitchen, Utility[Wash area], Bathrooms, and any other place that requires internal plumbing are considered. Now based on the points where you need connection the plumber works out the plumbing work. It is good if your architect can provide plumbing drawings, it will be cleaner that way. Else the plumber himeself works out the pipe layout. He needs one pipe of hot water and one for cold water connection. He needs to mark and cut grooves in the wall for these pipes. The water connections are made using CPVC pipes.

Sewage connections are done in the flooring of the bathrooms for human waste and utility/kitchen areas for waste water. PVC pipes of 2 inch, 4inch or 6 inch thickness are used for sewage purpose. The ends of the pipes are fitted with traps if on the ground.

Try to ensure the following in bathroom connections

1. Solar connection and geyser connection requires 2 stop cocks/valves. Here is the details for why we need 2 for hot water connections.
2. Mixers come as the traditional two knobs – hot and cold[last preference], single lever mixer[second preference] or thermostats[ my first preference although expensive]
3. Take sufficient pictures for your reference once plastering is done. Else you will be searching in the dark for where connections are present after few years.
4. Plan your tap points well.
5. Make sure to have a sewage point for waster water of washing machine in case at some point in time you need to place washing machine in your bathroom. [ see the picture ]
6. For wall mounted commodes you need to procure the wall mounted flush tank from Geberit or any other equivalent brand. [see the picture]

[Note that it would be a great idea to have the thickness of wall where pipes are more to be made in atleast 6 inch thickness so that the grooves dont impact the wall strength ]

Complete plastering but try to keep bathroom/kitchen pipe area plastering open.

Note that once external plastering is complete you can finish the external water pipes plumbing work. You can place the overhead tank and test the water pressure for any leakages in bathroom pipes. These can cause serious problems to your house if there is any leakage in water pipes once plastering is done. So my advice is to test water connections before internal plastering of bathrooms at the minimum. Also dont forget to test the hot water pipe as well because hot water pipes needs to be more secure for high temperatures.
Once plastering is complete and before pavement area work is started.

If a small amount of earth exacavation is required for the sewage pipes to be place, complete it. Place the pipes. Finish the drainage chambers.

Similarly place the pipe from sump to the road for the cauvery connection. Plan a small chamber for the cauvery meter connection. This should be towards your front gates and not inside of your building because the meter reader should be able to access it even if you are not at home. Else you have to run behind to get your readings done or be prepared for some approximate billing.
So here is the summary of what you have done and the flow of water and sewage!!!!
1. Cauvery water is connected to the sump.
2. Borewell and sump are connected to the overhead tank through two different pipes [preferred in case either water gets contaminated or dirty]
3. All your bathrooms, kitchens, toilets, utility area are connected to the overhead tank for cold water pipes.
4, All your bathrooms, kitchens, toilets, utility area are connected to the Solar water heater tank for hot water pipes.
4. All waste water and sewage pipes are connected to nearest chambers. All chambers are connected to the BWSSB sewage connection on the road.

Hope you have got a high level picture of plumbing activities in your building. Do leave your feedback and comments. Hope it is useful and please do follow my blog for more in-depth content in future!

Please do visit the various articles on “House Construction” and clear the basics.