Positive Input Ventilation Units Explained

A Positive Input Ventilation (PIV) unit is a system designed to improve indoor air quality by supplying fresh, filtered air into a building, typically a home. It helps reduce condensation, mold, and indoor air pollutants by continuously introducing clean air and expelling stale, moisture-laden air.

How Does a PIV Unit Work?

1. Air Intake & Filtration:

   • The unit is usually installed in a loft or high position within a property.
   • It draws in fresh air from outside or from a well-ventilated attic space.
   • The air is passed through filters to remove dust and pollutants.

2. Positive Pressure & Air Distribution:

   • The unit gently pushes the filtered air into the home through a ceiling-mounted diffuser.
   • This creates a positive air pressure inside the home, forcing out stale, damp, or polluted air through natural leakage points (e.g., gaps around doors, windows, and vents).

3. Humidity & Condensation Reduction:

   • By continuously replacing moist indoor air with fresh, drier air, the PIV system helps reduce condensation buildup, preventing mold growth.

4. Additional Features:

   • Some units come with built-in heaters to temper the incoming air during colder months.
   • Many modern PIV systems include sensors that adjust airflow based on humidity levels.

Benefits of a PIV System

✔ Reduces condensation and mold growth
✔ Improves indoor air quality by reducing allergens, pollutants, and odors
✔ Helps remove harmful gases like Radon (especially in some geographical areas)
✔ Energy-efficient compared to traditional extraction systems

PIV units are especially effective in older homes or properties with poor ventilation and condensation problems. Would you like recommendations on specific models or installation advice?