Positive Input Ventilation (PIV)

Positive Input Ventilation (PIV) systems create fresh and healthy living environments by supplying fresh, filtered air into a property at a continuous rate throughout a property and is our most popular method of whole house ventilation.

Positive Input Ventilation (PIV) is a whole house air ventilation system that works by drawing in fresh, filtered air into a property from outside. These can be either installed in a loft space or on a wall in a flat or apartment. They ensure that a continuous supply of air is supplied into the home to eliminate or significantly reduce condensation. 

Ventilation is the intentional introduction of outdoor air into a space and is mainly used to control indoor air quality by diluting and displacing indoor pollutants; it can also be used for purposes of thermal comfort or dehumidification.

To find out more about how PIV works, please watch this video.

All of our PIV units are designed to perform with extremely low noise levels, always ensuring the best level of whole house air ventilation is maintained.

Positive Input Ventilation is a whole-house form of air ventilation which is designed to supply fresh air to the whole property. In some cases, where there is a remote wet room (kitchen, en suite, bathroom, WC, or utility room) we also advise fitting extractor fans.

The units are either situated in the loft in a house, or on a wall in an apartment to deliver whole house ventilation. They operate quietly in the background, eliminating condensation and preventing mould whilst maintaining healthy indoor air. All of our PIV units are fitted with an ultra-low watt motor to ensure minimum energy consumption.

Did you know that 95% of our customers experience an improvement in condensation within one week after having a unit fitted?

A positive input ventilation system relies on a central unit which is mounted in your loft and connected to the exterior of your house and internal rooms via ducting.  As PIV systems require connection to mains electricity and involve the addition of vents into several rooms, they should be professionally installed to ensure that they work correctly and are safe.

In addition to the installation process, it is also important to plan how the PIV system will be configured in your home.  During a free home survey, our local ventilation specialists will assess your home to find out exactly what your ventilation requirements are and provide the right solution for your needs.

PIV systems work by drawing air into your home from outdoors rather than actively forcing the air out.  This means that the fresh air will mix with the air already inside the house and be warmed by it.

In a well-insulated home, the heat loss will be minimal, and the small additional cost of heating will be offset by the long-term benefits of reducing condensation and the problems that it can cause.

Unlike Positive Input Ventilation Systems (PIV) which actively pull air into the house from outside and use this increase in pressure to force damp air out, Continuous Mechanical Extract Ventilation (MEV) systems rely on a central extractor system which pushes air out of the house to be passively replaced by the fresh air from outside.

PIV systems can be installed in an existing home without the need for extensive building work, which can make them a much better choice in circumstances where you want to avoid the additional cost and inconvenience of a full renovation.