The necessary conditions for the wine conservation are, in order of importance :
The temperature of the storage area, which must be between 10 and 16°C. In this range, the temperature could be low or high but it would not matter, although the ideal temperature is 12°C. What is important, is to prevent the variations of temperature: not the slow seasonal variations, but mainly the daily variations. Better to have a hot cellar ( still below 17°C) but of which temperature is stable, than a cave of which temperature change from 12°C at night to 16°C at day; in a such cellar, the wine get quickly tired.
The storage area hygrometry , at a minimum of 70%; below 60%, the corks dry and let the air pass.
The storage area lightning : the wines (more for the white than for the red) fear the light. This one act as a chemical catalyst for some chemical reactions which decompose the colourants. The most actinic lights as the neon ones are the most harmful. The tinted glass of the bottle ensure a better conservation.
The absence of vibrations; speaking about that, note that the noise is source of vibrations. Be also careful to the subway vibrations frequent in the cellars of Paris.
The absence of smell (fuel, fruits, etc.). The smells are indeed able to infitlrate by the cork...
The above conditions are relative to the storage area. About the bottles, they must of course stay in horizontal position, in order to ensure to the cork the humidity it need to play its part.
A good solution for those who can not satisfy all these conditions: the purchase of a wine cabinet. More and more sophisticated, they are ideal to keep the wine in flat or in house without cellar adapted to a good conservation of the wine.
Source : La planète Vin et Version Vin