Supply Ventilation in an Apartment: Options, Pros and Cons

Modern apartments are often sealed with tight windows and insulated walls, which helps save energy but can worsen indoor air quality. Stale air, high CO2, excess humidity, and persistent odors are common signs that natural ventilation is not enough. Supply ventilation brings controlled fresh air into the apartment and can significantly improve comfort, sleep quality, and overall health. Option 1: Passive wall or window vents. These are simple air inlets installed in a wall or window frame. Pros: low cost, no complicated equipment, minimal maintenance. Cons: airflow depends on outdoor conditions (wind/temperature), limited filtration, possible drafts and noise if installed incorrectly. Option 2: Compact supply fans (decentralized units). These devices actively push air through a wall duct and usually include basic filters. Pros: more stable airflow, better control, improved filtration. Cons: requires power, can generate noise, filters must be replaced regularly. Option 3: Central supply unit with ducts (mini air handling unit). Suitable for renovations or new interiors. Pros: even distribution to several rooms, higher filtration classes, automation by CO2/humidity sensors. Cons: higher price, space needed for ducts and the unit, professional design and installation required. Option 4: HRV/ERV (heat recovery ventilation). It supplies fresh air while reducing heat loss by recovering energy from exhaust air. Pros: energy efficiency, comfort in winter, balanced ventilation. Cons: the most expensive option, more complex maintenance. When choosing a system, assess apartment area, number of occupants, noise requirements, and filtration needs (especially with allergies). A good setup is quiet, adjustable, and easy to service—because clean air should be a habit, not a hassle.