Positive Input Ventilation

Allow your home to breathe

what is Positive input ventilation?

The ultimate in condensation treatment, our positive input ventilation system is designed to provide a reliable solution to condensation, black mould and air quality issues within the whole property; ensuring that damp, stale air does not have an opportunity to fester within a home.

Lack of adequate ventilation and modern occupancy styles can lead to a build up of excessive humidity and moisture. This poor indoor air quality can lead to serious health issues for asthma and allergy sufferers and those with breathing difficulties. PIV units can provide a solution to improving the air quality in your home and avoiding any potential health issues that may arise. 

Contact our condensation experts today

How do pIV Units work?

The positive input ventilation system draws in fresh air that is filtered and dried at an ambient temperature. This dry air is then gently introduced into the property continuously creating positive pressure by diluting and displacing the stale, moist air that would cause condensation and black mould issues within the property.


The simplest way of installing a PIV unit is through loft installation, so properties with lofts are at an advatage. Loft instalation involves using the warm air that enters the loft and recirculating this air in the property to create positive air pressure. Although loft installation is the easiest method to install a piv unit, there are other methods available for homes without a loft.

If you live in a flat with no loft access a piv unit can be installed wherever a hole can be cut into the wall that allows the unit to be placed between the property and air source.

Types of positive input ventilation units

Two versions of our PIV units are available. Depending on the type of property really determines the best systems for you. They are mounted either in the loft or for flats and apartments in the central hallway.

Wise property care service


A loft unit is fitted in the roof void and ducted via an air diffuser, normally mounted in the ceiling above a stairwell. For units fitted with pre heat facility, the heater control switch is sited on the landing wall at a convenient height to enable the user to switch the heater on or off. Also, the fan speed control is set from this position.

Wise property care service


The flat unit is fitted on a convenient wall, as close to the intake point as possible. Ideally, the unit should be fitted inside a hall cupboard, where access to an external wall and ambient air is possible. Supply ducting is then run to an outlet air grille, normally situated in the hall, in order that the introduced air is delivered to a central point within the dwelling.

WHAT ARE The benefits of positive input ventilation?

  • DC motor for quiet operation
  • 5 year guarantee
  • Lower energy costs - keeping with Government directive regarding energy efficient appliances
  • Alleviates condensation
  • Alleviates black mould
  • Reduces radon
  • Low maintenance
  • Special large capacity filter to ensure maximum ventilation
  • Energy efficient - consumes as low as 6 watts
  • Robust construction

Getting A PIV UNIT installed

Wise Property Care will always carry out a thorough survey before recommending any condensation treatment, and the same goes for installing mechanical ventilation.

If you want one of our surveyors to see if positive input ventilation is right for you then call us today on: 08006522678 to book a survey. Alternatively, fill out or short contact form and one of ventilation specialists will advise on whether a PIV unit is right for your property. 

More about our condensation surveys