My son has just moved into a studio that lacks ventilation hatch especially above the cooking plates despite the windows always open persists still smells to note that this studio was originally an old building to make cider. His studio is in the part where there was the cellar, everything has been made to standards but how to mitigate the smell of contain? Also note that the former tenant smoked.
You do not specify if your son is a tenant or owner...
If the studio is in a low-ventilated basement, the walls may be damp and the smell lingering despite the opening of windows It will be necessary to first check and resolve any moisture problems. You can create a natural ventilation scheme by installing high air vents in the "dry" room (living room / bedroom) and low air vents in the wet rooms (kitchens, toilets, bathrooms). A space of at least 1.5 cm should be provided under the doors by planing them if necessary for ventilation to be effective.
Installing a hood in the kitchen can also help remove odors. Finally you can dry the walls by renting an electric dehumidifier, then paint them with a special anti-moisture paint from Dip'etanch.
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