Renovating a house improves its insulation and reduces heating needs. However, by making the building more airtight, the work also limits the natural renewal of air. Without proper ventilation, humidity and pollutants can accumulate.
In Switzerland, integrating ventilation from the design stage of the project is therefore essential. It helps maintain air quality, occupant comfort, and the building's durability, while avoiding compromising the performance achieved through energy renovation.
Why does a renovated house need to be ventilated?
In an old home, air often circulates through leaks in windows, roofs, or walls, causing significant heat loss. After insulation work and the installation of high-performance joinery, these infiltrations decrease significantly.
This improvement changes how the home functions. Moisture produced by showers, cooking, laundry, or breathing is less easily expelled. Odors and certain pollutants may also linger longer in the rooms.
Regularly opening windows is still useful, but it does not guarantee constant renewal. Well-designed ventilation ensures a more regular and controlled airflow.
Preventing humidity and mold
Excess humidity can lead to condensation on windows and cold surfaces. Over time, mold can appear and degrade the finishes.
The risk must be particularly monitored after partial renovation. For example, replacing windows without addressing certain thermal bridges can shift condensation to the coldest areas of the walls.
Ventilation removes excess humidity before it settles on surfaces. However, it does not replace the treatment of an infiltration or insulation defect: the entire situation must be analyzed coherently.
Improving indoor air quality
The air in a home can contain carbon dioxide, dust, odors, and various compounds. An appropriate system introduces fresh air into living spaces and expels stale air from the kitchen and bathroom. This limits the feeling of stuffy air without leaving windows open for long periods in winter.
Which system to choose for a renovation?
The choice depends on the configuration of the house, its level of insulation, available ducts, and the extent of the work.
A single-flow ventilation system extracts air from humid rooms, while fresh air enters through openings in living spaces. Easy to implement, it does, however, expel some of the indoor heat.
A double-flow ventilation system recovers heat from the extracted air to preheat the incoming air. It limits energy losses and can filter outside air, but requires more space, well-designed ducts, and regular maintenance.
In some projects, a decentralized solution may be considered when installing a complete network is difficult. A technical study is necessary to properly size the flows, choose the location of the outlets, and limit noise disturbances.
An installation to plan from the start of the project
Ventilation must be anticipated alongside insulation, heating, joinery, and interior layout. This coordination facilitates duct passage and avoids costly modifications.
Once installed, it must also be maintained. Cleaning the outlets and replacing filters, when present, helps maintain good performance.
With Avenir Rénovations Suisse, your Project Manager studies your home, defines suitable solutions, and coordinates the necessary professionals. You benefit from a single point of contact to integrate ventilation into a comprehensive renovation, respecting the requirements applicable to your project.
Do you want to renovate your house while maintaining healthy indoor air? Contact Avenir Rénovations Suisse for a personalized study and a tailored quote.
