When you build your house, there are two things you need to consider if you want to ensure maximum comfort in a tropical climate. The first is to keep the rain out to the greatest extent possible and the second is to avoid buildup of heat from sunlight.

In the Indian sub-continent, the monsoon for the most part, blows in from the south - west. So if you want to protect your house from the driving rain, it makes sense to have a site that slopes away (towards the north-east), rather than one that takes the downpour straight in the face. Also the windward face will tend to receive driving rain.

On the leeward side of a hill, the rain becomes more vertical and can be easily blocked out using vegetation or architectural features like awnings and recessed windows.

As far as the amount of light and heat is concerned, it depends a lot on the orientation of a sloping plot. In countries such as India, land sloping away from the equator (in the south), receives much less solar radiation than one that slopes north. Let us carry that rule further. Since the hottest time of the day is when the sun lies in the south-west, the ideal slope is once again, towards the north-east.

This, in fact, is exactly what the Vastu Shastras advise us to look for in a piece of land that we wish to build upon. The only difference is that three thousand years ago, they gave religious reasons for doing so. The layman of that time wasn't going to listen to some mumbo-jumbo about the "cosine law of solar radiation".

Now if you have already purchased or selected a place where the levels do not conform to the ideal, you can still minimise the problem. Take precautions like creating deep roof overhangs and awnings and grow a barrier of evergreen trees along the south and west boundaries. Best of all, use the "inauspicious" levels as a bargaining point with the estate agents. Serves them right for foisting the Vastu bogie on us in the first place.