Positive Input Ventilation (PIV) systems are designed to improve indoor air quality by introducing fresh, filtered air into a home and expelling stale, moist air. They are an effective way of improving the indoor air quality in your home as well as preventing condensation from becoming a problem.

PIV systems are highly energy efficient in use and provide fresh air throughout your property to reduce humidity and the concentration of unwanted pollutants, including Volatile Organic Compounds (VOCs), pollen and other allergens, and radon gas.

PIV System Operation

PIV systems such as envirovent ATMOS draw in fresh air from outside the home, usually through a central unit installed in the loft. This air is filtered to remove pollutants and allergens.

The fresh air is gently distributed throughout the home via a diffuser, usually installed in the ceiling of a central hallway or landing. This ensures a consistent flow of clean air, reducing humidity and preventing condensation and mould growth.

The continuous supply of fresh air from the Positive Input Ventilation system creates a slightly higher air pressure within the home. This positive pressure pushes the stale, humid air out through natural ventilation points in the building's fabric, such as air bricks and vents.

PIV system installation

PIV Systems are connected to the mains electricity supply in your home and, as such, should be installed by a professional to ensure that they work as expected.

The first stage is for a ventilation specialist to assess the property so that they can determine the best location for the PIV unit and the most effective way to distribute the fresh air.

The central unit of the PIV system is normally installed in the loft. Air quality at roof level is higher because any heavy pollution – such as traffic fumes – or radon gas - tends to remain close to the ground. A roof vent is fitted so that air can be drawn into the home and filtered.

The central unit is connected to a diffuser via ducting from where fresh air is distributed throughout the home.

Once installed, the system should be commissioned and tested to ensure that it is working correctly and that the homeowner has full instructions on how to maintain the system over time.

Is a PIV system right for your home?

envirovent offers a free home survey in which a ventilation specialist from your area will visit your property and identify the causes of humidity and advise about the best solution for your needs.

PIV systems are particularly beneficial in homes with High Humidity. The systems are highly effective in reducing humidity levels, making them ideal for homes that suffer from condensation and mould problems.

In homes with inadequate natural ventilation, PIV systems can significantly improve indoor air quality by providing a continuous supply of fresh air.

The improvements in indoor air quality that PIV systems can offer make them ideal for people who suffer from allergies such as hay fever. The filtration system in PIV units removes allergens and pollutants from the incoming air to significantly reduce the concentration and alleviate symptoms.

PIV systems can help improve the energy efficiency of a home by reducing the need for heating. By maintaining a consistent flow of fresh air, they help to prevent the build up of moisture and damp, which can make a home feel colder.

Find out more

If you have a persistent problem with condensation, damp or mould in your home, a PIV system could help.

Contact Us and one of our local ventilation experts will visit your home, identify the causes of poor air quality and high humidity, and provide you with advice about the best solution for you.

How Positive Input Ventilation Systems Work

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