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Water management
Consumption of drinking water has become the second most expensive cost at home, after energy. Application of water management to buildings will reduce water quantities to be treated, improve the quality of water, and reduce costs. The first step in better water management is to reduce drinking water leaks. In France, these costs are estimated at more than 1.2 billion m³ each year, almost 20% of consumption in the domestic sector. A leaking tap wastes 35 m³ per year, and a leaky toilet flush tank wastes 145 m³.

Possible improvements for water management are related to:

• variable volume of water flushes,
• a pressure reducer,
• short pipes,
• recovery of rain water,
• individual metering.
  

Wind pressure
It is possible to increase the dissipation of heat from a building using the wind pressure effect. When wind strikes a building a high pressure on the exposed side and a low pressure on the opposite, sheltered face results. Usually, the speed and direction of local winds are variable. At an individual site however, a building can often be positioned in relation to neighbouring buildings, planted vegetation and other obstacles so that a wind is induced in a known constant direction at a reasonably steady rate. The conditions for ventilation are best when the wind strikes the building at an angle of up to 45 degrees.

The movement of air across a site is from high pressure zones to low pressure zones, through openings in the building envelope. The size and position of the openings determines the speed and direction of air movement within the building. The air speed is greatest when openings by which air leaves the building are bigger than air inlet openings, however inlet openings must be of adequate area. The best distribution of fresh air throughout the building is achieved when the openings are diagonally opposite each other and air flow is not hindered excessively by partitions and furniture, etc.

Maximum ventilation should be provided during the day in occupied areas of the building at head height. In addition, there should always be a good flow of fresh air along the building's most massive elements so that as much heat as possible is dissipated from them.