Leakages in terraces, bathrooms, toilets, and walls are common problems of buildings. This will lead to dampness, which may further give rise to problems in electrical installations, fungus growth, and other unhealthy conditions for people residing there.

• Waterproofing is a skilled job and it is dangerous to get such work done from small time contractors who may not have adequate knowledge in this field.
• Other reasons like poor quality of bricks, sand, concrete, plumbing defects, etc. can lead to leakage problems.
• Materials used for waterproofing should be strictly used in same proportions and quantities, as suggested by the manufacturer or consultant.
• For making more profits and save costs on these materials, many contractors often play mischief in material usage.

It is a common observation that severe leakage through the toilets and bathrooms of one flat in a building leads to nuisance to lower floor occupants.

Invariably there are no spare toilets and rectification of leakage cannot be done within a short time.

95% of the problem can be rectified without removing the tiling / pans etc.

This is because over the years of continuous usage the joints between the tile and W/C pan, joint between the pan and trap below, joints between the door frame and flooring allow the water to seep below.
These are required to be attended regularly. Ideally this exercise should be undertaken every year.

Procedure to be followed is as follows:

• Take one toilet or one bathroom at a time.

• Seal all the tile joints with tile jointing mortar.

• In case of bathroom, check the nahani trap.

There is usually a gap between the jalli and the trap. This is normally plastered. There are invariably cavities in these gaps. This should be inspected. The entire cylindrical portion should be replastered with polymer modified mortar made with 1:2 cement + fine sand mortar with 15 % polymer additive by weight of cement.

• For Indian W/C also the joint between S trap and W/C pan should be sealed with a suitable epoxy sealant after sealing all the tile joints with mortar.

In case the above procedure does not give results of reduction in seepage or wetness in 15 days then the entire W/C or Bathroom is required to be opened up waterproofing and tiling has to be redone. The procedure for waterproofing of sunk portion is same as brickbat coba or ferrocement waterproofing of terraces.
The floor of the WC, bathroom etc should be sloped away from the door towards the outlets.