To avoid ugly water marks of muddy rain water on the underside of overhangs or chhajjas the following ought to have been done at the stage of plastering of the overhang or chajja. However, if you discover any overhang without a drip or tapak, a mason can always be engaged to add a drip (locally known to masons as a tapak) to the overhang or chajja. A drip (tapak) is an extra bit of thicker plastering on the underside of the overhang or chajja just below its periphery. The drip is usually about half an inch wide (12 millimetres) and is thicker than the normal plastering of the surface by about a few millimetres. In the absence of a drip, the rain water dripping on the vertical face or thickness of the chajja will tend to travel back along the underside of the plastering of the chajja. This is what leads to water marks. A drip or tapak, being a thicker edge of plastering under the tip of the periphery of the overhang or chajja, breaks the passage of water along the underside of the chajja, ensuring that all the water droplets drip down at the point at which this drip ends on the horizontal plane. Therefore, since no water would travel beyond this point horizontally towards the rest of the underside of the chajja, there will be no water marks on the underside of the chajja. Any mason would be able to do this and solve the problem of the ugly water marks.

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