Positive Input Ventilation (PIV) systems supply fresh, filtered air into a property from a central location to help displace stale, moist air.
The ATMOS® range are loft mounted Positive Input Ventilation (PIV) systems that are designed to reduce mould and condensation and improve indoor air quality within a property.
The ATMOS® DUAL range are loft mounted Mutiple Input Ventilation (MIV®) systems that are designed to reduce mould and condensation and improve indoor air quality within a property.
The ATMOS® AIR range are loft mounted Positive Input Ventilation (PIV) systems that are designed to reduce mould and condensation and improve indoor air quality within a property. ATMOS® AIR can supply filtered air from the loft space or directly from atmosphere depending on conditions.
The ATMOS® AIR DUAL range are loft mounted Multiple Input Ventilation (MIV®) systems that are designed to reduce mould and condensation and improve indoor air quality within a property. ATMOS® AIR DUAL can supply filtered air from the loft space or directly from atmosphere depending on conditions.
The ATMOS® WALL range are wall mounted Positive Input Ventilation (PIV) systems that are designed to reduce mould and condensation and improve indoor air quality within flats or apartments.
The Positive Input Ventilation (PIV) loft mounted systems are designed to reduce mould and condensation and improve indoor air quality within a property.
The Multiple Input Ventilation (MIV®) range are loft mounted systems that are designed to reduce mould and condensation and improve indoor air quality within a property.
The Positive Input Ventilation (PIV) AirSource systems are designed to reduce mould and condensation and improve indoor air quality within a property. PIV AirSource can supply filtered air from the loft space or directly from atmosphere depending on conditions.
The Multiple Input Ventilation (MIV®) AirSource range are loft mounted systems that are designed to reduce mould and condensation and improve indoor air quality within a property. MIV® AirSource can supply filtered air from the loft space or directly from atmosphere depending on conditions.
PIV is a whole-house ventilation system that gently supplies filtered air into a property at a continuous rate from a central location. This solution can easily be retrofitted and often doesn’t even require a duct to atmosphere. Instead, it relies upon air naturally entering the loft space, as well as solar gain, before this is positively pushed through the property, forcing stale, moist air out through cracks and leakage points.
PIV systems are offered with a variety of filters, including some with fine particle or even carbon filters, depending upon property requirements and location. There are Positive Input Ventilation units available for properties with and without a loft space, with many including a pulse heater to temper the incoming air for comfort during periods of colder weather. A summer shutdown function can also be offered to prevent the tempered air from entering the property during warmer weather. These units are offered with a variety of controls, including wireless, a 0-10V sensor port and app options.
Frequently Asked Questions
PIV stands for Positive Input Ventilation, an alternative type of ventilation system in a home.
PIV systems provide fresh, filtered air into a property from a central location, often on a landing. The units come with a pulse heater to temper the air, which is then positively pushed around the property, replacing stale, moist air with renewed air. This circular process continues, helping to reduce condensation and mould in the property.
Positive Input Ventilation systems will ventilate all rooms directly linked to the PIV unit. If the unit is located in a central position, this should cover the majority of rooms. However, if you have to walk from one room to get to another, such as an en-suite, or a kitchen or other wet room not connected to the hallway or central space, then that rwet room needs an additional continuous ventilation option, such as a d-MEV.
All PIV units offered by EnviroVent include a filter. These vary in grades, depending upon the requirements of the property or unit, but are generally offered with a minimum of an ISO Coarse 65% grade as standard, unless otherwise stated.
A Positive Input Ventilation unit can be installed in a three-storey property providing the layout allows this. However, there are requirements regarding protected areas in a property with a height of 4.5m or above, which need to be taken into account. A wireless PIV system with specialist metal diffuser will be required in such a scenario. Please get in touch with our Technical Department on 01423 810810, choosing option 5, to discuss fire-stopping requirements further.
A Positive Input Ventilation system can be installed in a property without a loft or low apex. However, a wall-mounted PIV unit will be required. If this is something you're considering, please get in touch with EnviroVent on 01423 810810.
Although a Positive Input Ventilation unit comes with a pulse heater, this is used to temper the air should the temperature outside drop, but it's not a form of heating to be used within a property. If the temperature in the property exceeds 25°C, most of EnviroVent's PIV units will go into sleep mode to prevent excessively hot air from entering the property. They will switch back on when the temperature drops. If the unit is ducted to atmosphere, the unit will continue to run all year round.
There are several types of PIV units available, including those with wireless and app controls, with multiple input for longer or L-shaped landings, or if there's a specific issue with ventilation in a part of a property. There are also units ducted to atmosphere in areas of high radon, or any other requirements.
PIV units provide fresh, filtered air into a central space in a property, whereas centralised MEV units extract stale, moist air from several wet rooms within a property. A PIV system can be retrofitted into a property without necessarily requiring ducting, whereas an MEV unit can require significant works within a property to run ducting between each wet room.
PIV systems are suitable for most properties, providing there's enough ventilation within the loft itself, there's a central location where the unit can be installed in the property, and the property can meet the airflow requirements using PIV as a ventilation solution. This wouldn't be a suitable solution for extremely airtight properties, as there's a need for airflow between rooms and atmosphere.
A Positive Input Ventilation unit needs to be installed by a person competent to do so. The installation of a PIV system involves an electrical connection and the setting up of the unit to meet the property's requirements. Please call EnviroVent on 01423 810810 for any installation queries or to request a free home survey.
PIV systems generally run all of the time, with the exception of units that go into sleep mode during hot weather periods. These units are designed to be unobtrusive and provide fresh, filtered air into the property.
