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Positive Input Ventilation

Cure Severe Condensation with Positive Input Ventilation

The Positive Input Ventilation (PIV) principle provides whole home ventilation and an effective method of curing condensation problems in the home.

This form of ventilation is becoming increasingly recognised as the best value approach to ventilating homes and preventing severe condensation and mould. Essentially, the concept is to introduce air to the home at a continuous low rate, encouraging movement of air from inside to outside. A single unit situated in a loft space will normally be sufficient to continuously dilute, displace and replace the old contaminated air with drier, tempered and filtered air. The result is a significant contribution towards providing a healthy, condensation-free home.


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How PIV systems work

Unlike extract systems which draw in unheated, unfiltered air, a Positive Input Ventilation (PIV) unit gently supplies tempered, filtered air into the home. It does this by using otherwise unused heat within the roof.

There are many benefits of this system. Firstly, a significant proportion of external pollutants are prevented from entering the home. Secondly, the use of otherwise unused heat in the roof results in the ventilation unit providing a significant net energy gain to the home. Finally, there’s no better way to ventilate a home than from the inside out via a single centrally-located supply air diffuser.

A properly designed and installed unit will ensure that old, contaminated vapour-laden air is continuously diluted, displace and replaced with good quality air. The result is improved air quality and an environment in which condensation dampness can’t exist. The installation of a low energy positive input ventilation unit will ensure that the air in your home is completely replaced 20 times a day, which is the recommended rate to maintain good air quality.

PIV redistributes heat from ceiling level

Input air is directed across the ceiling (usually in your hallway). This uses a scientific principle called the Coanda effect, which has the impact of mixing with the wasted warmer air that has risen above head height in your home. It therefore increases the efficiency of your heating system. Severe condensation and black mould is caused by poor ventilation and heating. Water forms on windows and walls and if left untreated, will result in black mould or mildew growing on walls and furniture.

Health benefits of PIV

It’s estimated that around 80% of asthmatics are allergic to dust mites (or more specifically to the faeces of these creatures). Dust mites are too small for us to see but they can be present in huge quantities in soft furnishings and more worryingly, in mattresses and pillows. The faeces can also float in the air when you shake your bedding or walk over the carpet where they’ve settled. It’s the inhalation of this allergen that can trigger an asthma attack. Dust mites breed best in a humid environment – just the sort of environment you’ll have if your home is poorly ventilated. Ventilating a home can create a hostile environment for the dust mite which means populations fall and faeces production is reduced.

Clinical research has proven that whole home ventilation can play a significant role in controlling dust mite allergens. Nuaire’s own experience through hundreds of reports from satisfied customers who claim significant relief from their condition, backs up this research. NB. Nuaire do not claim that the use of their products will cure asthma or eliminate asthma.

Biocraft offers and range of products and services to prevent condensation, black mould and the problems associated with poor indoor air quality. We also supply and install a range of PIV ventilation and condensation control units throughout Berkshire, Hampshire, Surry and Oxfordshire.


For more information, please call 0800 781 8358 or email [email protected].