Cassandra Delli Colli and Jean-Louis Pelletier were on the same wavelength when they bought their house in Boucherville earlier this year. Both wanted to improve the energy performance of their home as soon as they took possession of it. They started by fixing the flaws hidden behind the walls.

Such a decision helps increase the value of their investment, argues Cassandra Delli Colli, who works for a financial institution. This also allows them to live in a healthy and comfortable interior, adds his partner, a mechanical engineer, who manages various mechanical systems in the factory where he works, and wants to have a quality environment at home.

They fell under the spell of a cottage located a street from the gentleman’s old house. Madame fell in love with the ground floor, with its open concept, recently renovated. He is very happy that the heating and air conditioning system dates from the construction of the house, in 1986. He will thus be able to replace it with a system that interests him.

“We bought the house for a minimum of 25 years,” explains Jean-Louis Pelletier. Now is the time to invest to be able to save over a longer period of time. »

Out of curiosity, during their purchasing process, the latter went on YouTube to see high-performance homes in the United States and Canada. He discovered AeroSeal and AeroBarrier technologies, which eliminate air leaks by sealing ducts and building envelopes.

Two months before taking possession of the house, scheduled for July 22, he contacted Aeroseal Global in the Montreal area. He only had two days to get the work done, but he was willing to do the required preparation himself.

“It’s easier to do when the house is empty, because you have to cover all the horizontal surfaces,” says Cassandra Delli Colli. Our friends and families helped us. »

For two days, eight of their loved ones took turns to give them a helping hand. It was necessary to protect counters, floors, stairs with large rolls of brown paper, wrap toilets, showers, faucets, door handles with plastic wrap, mask the tops of doors, etc. , on three levels (basement, ground floor, upper floor).

“We were ready to think outside the box,” says Jean-Louis Pelletier. In total, it required 100 hours of preparation, counting everyone’s contribution, on Saturday and Sunday. »

“Before, a lot of heat or cold was lost in the walls,” he adds. Now it goes straight into the rooms. The temperature is therefore better controlled and more stable in the house. »

The next day, it was the turn of the envelope of the house to be sealed. Once the infiltrometer was installed, as during an airtightness test, the fine particles projected blocked countless holes, often tiny. The process also made it possible to detect the presence of larger openings, which the owner has since sealed. “On a screen, we could see the size of the leaks decreasing in real time. We started at approximately 4.12 air changes per hour, with a total of 212 sq. in. of holes, and reduced that to 126.2 sq. in. of holes, and 2.45 air changes per hour. air on time. That’s a 40.6% reduction in air leakage. My goal is to go below 2 air changes per hour. »

He actually wants to bring the house to the level of Novoclimat 2.0 certification. There are therefore several steps to take: change the heat pump, install a heat recovery ventilator, insulate the attic and the floor joists, as well as install a radon evacuation system.

An investment of approximately $40,000 is planned. According to the couple’s calculations, taking into account subsidies, energy efficiency improvements, inflation and electricity price increases of 3% per year, the break-even point will be reached after 18 years .

The comfort gained by carrying out all the work, however, is priceless.

Want to learn more about energy-efficient home renovations? To launch the festivities surrounding its 30th anniversary, the magazine La Maison du 21e siècle is organizing a series of three conferences given by experts, on the theme “What to do with our old buildings”. The first conference, on October 26, will focus on insulation and waterproofing. This will be followed on November 9 by a conference on high-efficiency heating. On December 6, it will be about producing and storing your own solar electricity. The conferences will be presented free of charge at the Maison du développement durable, at 7 p.m., as well as on the web live and rebroadcast on the YouTube channel.