LEVELS OF PERFECTION: A good construction demands road, site and building harmony. Image Courtesy: The New Asian Houses
If the building can be compared to the processor of a computer, the site is the motherboard and the other services are like the accessories and the peripherals.
We have mentioned it earlier as well that the road levels raise by about 3" once in every two to three years, so the finished floor level has to be raised by 3'0" minimum from the highest point on the road level. Along with the building, the site also has to sufficiently keep clear from the raising road levels. Some of the aspects of the site, which are essential and important for the proper working of a building are discussed below:
Under Ground Sump (UG Sump): An under ground sump is a temporary storage place, before the water is moved to the overhead tank for usage. The water to be stored in the UG sump is usually from water tanker lorries (which come in modules of 4000lts/8000lts/12000lts) or from the metro water supply. The metro water supply pipelines are usually laid 4'0" below the road level, hence the sump has to have a storage capacity below the inlet pipe level.
A hand pump can also be introduced at the metro water entry point with a valve arrangement that facilitates one to check whether the sewage gets mixed with drinking water. This helps prevent the little sewage contaminating the whole of the sump water. As for the construction of the sump itself, in clayey soil conditions an RCC sump with the raft foundation may be ideal, but if you wish to reduce the cost the sump can be built with a 9" brickwork and lined with a 3" thick RCC mesh work, which would avoid cracks. As an additional feature the sump top slab can be provided with a small peep hole 6" in diameter with a wooden cover and a small hooking rod for easy opening.
Bore Well: Water scarcity has driven many to the bore well option but in Chennai bore wells are about 60'0" to 100'0" deep, and many areas need to be deeper as the water bed sinks deeper in summer. The side setbacks where the bore well is to be proposed needs to be planned so that the boring equipment can be moved if it is necessary to <243>deepen the borewell at a later date. Simultaneously, providing rainwater-harvesting pits near the bore well recharges them as well.
Electrical cabling: While doing the electrical cabling conduiting at least 3 nos. PVC pipes should be planned at the entrance below the ground level to facilitate the inlet for electrical cable entry, telephone cable, broadband internet lines and TV cable entry.
Earthing Pits: Several electrical gadgets/ fixtures are being used but unfortunately proper earthing pits are not provided in most of the buildings.
For ideal earthing, the pit has to be filled with blue metal or coal, salt and sand, approximately 600mmx 600mm and has to be a minimum of 2 m and an ideal 3 m deep.
Sewage lines and inspection chamber: Similarly the planning of the sewer lines requires a detailed study and a lot of experience.
The height of the manhole over the inspection chamber are to be worked out because during the rainy days many of the sewers get clogged and there would be a chance of a reverse flow of sewage water and waste. Proper chamber levels would ensure this does not happen.
Overhead tank: The overhead tank should have a separate partition for bore well and corporation water, because in most cases the corporation water quality and the bore water quality do not match. In case the bore well water has a high iron content (which discolours the ceramic tiles and fixtures) then a slow sand filter or even a small treatment plant can be opted for at a nominal cost.
The author is the chief architect of Murali Architects, Chennai