FloPlast Pushfit Air Admittance Valve - 110mm Grey

Air admittance valves are an ingeniously designed fitting that avoids the need for a soil vent pipe to terminate externally and within the strict traditional guidelines that govern position.Traditionally, open vent pipes needed to be installed at least 900mm above any opening into the building that is within 3 metres of the vent pipe. This was to prevent foul odours from entering the living space. The beauty of air admittance valves is that they allow air to be drawn into the pipework to prevent pressure build up, but crucially no foul odours can escape from the system.This means that an air admittance valve can now be situated anywhere in the above ground drainage system provided it is at least 200mm above the highest wet entry point of the soil vent pipe (the wet entry point is the highest point of the soil pipe system that waste water can flow into).