While heatwave episodes are increasing, millions of French people live in housing that regularly exceeds 30°Csometimes several days in a row. Faced with sleepless nights, fatigue, fans at full blast and energy-consuming air conditioners, summer discomfort has become a public health issue as much as purchasing power.
However, it is possible to keep your home cool without systematically use air conditioning. “A well-insulated house stays cool in summer. Before you think about cooling the air, you have to keep the heat out”recalls Charles Saudubray, general manager of HomeServe Renov’. Insulation, solar protection, night ventilation or double flow VMC…, here is an overview of the most effective and economical levers.
Insulate and protect: the first shield against heat
The first air conditioning is the building itself. Working on the housing envelope remains the most sustainable way to limit overheating. Exterior insulation to eliminate thermal bridges, insulation of attics and low floors, often neglected but very effective, or even slopes under the roof for the top floors, this work makes it possible to maintain nighttime freshness longer. But not only: “glazing is often the thermal weak point of a home”underlines Charles Saudubray. Solar films and roller shutters with insulating blades, lowered in the morning, greatly reduce heat gain by radiation.
Focus on night ventilation and double flow VMC
Renewing the air is still too underestimated a lever. Many homes are poorly ventilated or equipped with outdated VMC. The humidity-controlled VMC, which automatically adapts to the humidity level, improves air renewal with controlled consumption. In summer, the double flow VMC goes further: it recovers the coolness of the night to precondition the air in the home before the hottest hours. Combined with a natural ventilation early in the morning and late in the evening to create drafts, it allows the felt temperature to be lowered by several degrees, without air conditioning and at a much lower cost.
Clever daily gestures to gain a few degrees for free
Beyond the work, simple reflexes effectively complete the system. Ventilating during the coolest hours, then closing shutters and blackout curtains during the day allows “store freshness”insists Charles Saudubray. In the kitchen, the traditional oven can increase the temperature of the room 3 to 4°C : “it is better to use microwaves or steam cooking or replace your bulbs with LEDs, which limits heat release”. Certain gestures also improve individual comfort: “take a lukewarm shower before sleeping to lower body temperature, cool your sheets for a few minutes in the freezer or place a bottle of iced water in front of a fan”. These are a few simple steps for an immediate “home air conditioning” effect at very low cost.
