The virtues of ventilation in a home are clear: ventilation eliminates moisture, prevents mold, removes odors. Zoom on the different breakdowns or VMCs possible ...
If, for a long time, the natural permeability of the houses or the opening of the windows from time to time was enough to make an atmosphere more breathable, this is no longer the case with modern constructions, especially those aimed at low consumption. or passivity. In the context of RT 2012, insulation and waterproofing are more than ever on the agenda. Permanent and controlled ventilation has become necessary. This is the famous VMC (controlled mechanical ventilation).
Basic model: the VMC simple self-regulating flow
Extraction vents located on the ceiling of the sanitary and the kitchen suck the polluted air. This extraction creates a depression in the house, which causes the aspiration of the outside air by natural entries and admissions of air disposed at the bottom part or integrated with joinery. Let's be clear: if this system is not expensive to install, it is insufficient today. It does not take into account the indoor humidity and its 24-hour operation consumes a lot of energy to warm the cold air that constantly enters the house.
More serious: the VMC simple humidity-controlled flow
The air intakes of the toilets and the kitchen are equipped with a sensor that reacts and adapts the air intake to the number of occupants and the humidity rate of the premises. This system offers a better management of the losses due to the renewal of air, and an energy saving of about 6%. Which is acceptable in the old, but remains insufficient in the new.
More sophisticated: the VMC double flow with static recuperator
The extraction vents located in the sanitary and kitchen suck stale air. It passes through a heat exchanger that recovers calories to transmit them to the air drawn outside, which is then sent to the living rooms. This energy recovery which can reach 60 to 70% allows a saving of heating of nearly 15%. Its disadvantage: the price. About 5 times more expensive than simple flow ventilation. And a complicated installation in renovation (attics or false ceilings necessary).
The top: the VMC double thermodynamic flow
It provides three functions: ventilation, air purification, thermal comfort. Its asset: a reversible thermodynamic power plant (a kind of mini air-to-air heat pump) that recovers calories from the air extracted in winter, and can produce cold in summer to cool the atmosphere. The only obstacle to its installation: the implementation is complex and expensive.
Good to know
Can a ventilation replace a heating system? Yes, under certain conditions. Thus, in the BBC housings, that is to say perfectly insulated and sealed, the "Domestic Temp. T.Zen 3000" system of Aldes (opposite), ensures, in addition to the double-flow ventilation, heating and cooling. refreshment.