They open the doors of their passive house – Economy
“I always needed air to open the windows. Well, I adapt! “, smiles Swann (18 years old). Since the spring of 2022, his family has been living in Plourin-lès-Morlaix (29) in a passive house consisting of a 100 m2 wooden cube on two levels, open to the south and west.
“We warm ourselves with the sun coming in through the triple-glazed windows. The house is very well insulated and airtight. During the wind tunnel tests, the only loss represented the diameter of a 5 centimeter coin,” says his father Gilles. And at the same time, “the air is renewed without opening the windows, with double-flow ventilation: internal calories are recovered by a system of filters and re-injected from outside air costs,” he adds. forty years old.
“The Incredible Power of Isolation”
Ambient temperature 19°C, without heating, on this cool Wednesday in December. CO detector2 pushes the vent to clear the air. Total electricity bills are down to €40-€50 per month, compared to €190-€200 in previous all-electric Neo-Breton homes, “still renovated to standard”. The bill even went up to €400 per month on a thermal sieve rented during construction.
Gilles and his partner Catherine invested 200,000 euros in this passive house: “We had our doubts about the passive house, we hesitated with the bioclimate and then we told ourselves that it has been around since the 1970s and it is worth giving it a go. Try it even if it costs 15-20% more than a regular apartment, mainly due to the quality of the insulation.” “The most important thing was that we wanted to reduce our energy footprint and bill. “My big discovery is the incredible power of insulation,” says Catherine.
The couple turned to the Approche éco-habitat network, first selecting a custom-designed home tailored to their needs and virtuous ambitions. Due to cost, the manufacturer finally turned to Akabois and chose a model in about fifteen while customizing it a bit.
From December 4th to 11th, a very cold week in Brittany, we spent an average of €3 per day, in November we were €18 for the month, and in January we were €100.
“The difference compared to our previous residences is that we are neither hot nor cold,” emphasizes Catherine. “When using it, you don’t feel the feeling of restricted air, more like a different air conditioner feeling. There is a small wind tunnel effect,” adds Gilles. An app helps with this adjustment, including directing the slats of the blinds according to the intensity of the sun.
“More comfortable than expected”
The same ability for programming and thermal control between pensioners Marie-Elisabeth and Jean. They built a timber-frame house in Combrit-Sainte-Marine (29) in 2017, designed by architect Jean-Charles Castric. L-shaped plan of 150 m2 with a roof height of 6 m in a large living room of about 60 m2. Practically passive living space surrounded by a hermetic heat and acoustic cocoon, equipped with triple glazing, double flow ventilation… and five interconnected low power radiators. Wide openings on the south side, windows facing the surrounding nature on the north side.

Five years later, “it’s even more comfortable than you can imagine. It was a discovery, this atmosphere that feels good everywhere with the same temperature in all the rooms,” says Marie-Elisabeth. “It’s true that we invested a lot in openings and insulation, and even if we had the budget to follow the architect’s proposals thanks to the sale of our old house, the depreciation will be long. and because we built part of our old house. land. We had fun,” he admits with Jean.
“Great comfort”
The annual consumption of electricity for heating in these southern Finistère conditions ranges from €278 to €399. “From December 4th to 11th, a very cold week in Brittany, we spent an average of €3 per day. In November, we were at €18 for the month, and last January at €100,” explains Jean, who allows you to set the ambient temperature in the app.
“It keeps hot or cool very well. For example, last summer we never exceeded 27 degrees in high temperature. This is a huge relief. It’s even a bit tiring when you go to someone else’s house and get a draft like it was in our previous house, “concludes the pensioner.