As most people are aware, the flood level of a fixture (such as a wash basin) is the level at which water will begin to overflow – this could be various reasons, including a blockage in the pipe, or quite simply due to the tap having been left turned on with the plug in.
Air Admittance Valves (AAVs) are used in place of traditional secondary ventilation, not only providing savings in materials and installation time, but also superior drainage ventilation – ensuring that trap seals are fully protected, resulting in keeping bad odours within the drainage system and eliminating gurgling. The installation position of the AAV in relation to the flood level is critical.
As illustrated in the below video link, where low quality AAVs (‘B’ rated in accordance with EN12380) are used these have to be installed ABOVE the flood level of the fixture. This is because they are not able to withhold the pressure of rising water due to a blockage and they effectively become the location of the flood level. This means that additional, and commonly unsightly, pipework needs to be installed to be able to reposition the AAV above the flood level of the fixture, and thereby prevent the risk of water from flooding into the living space through the AAV.
By contrast, the Studor AAVs (which are ‘A’ rated in accordance with EN12380) are manufactured to high standards which ensure that they may be installed BELOW the flood level of the fixture up to 1 metre below, as they will not leak and will withhold the pressure of risking water due to a blockage – they are tested to 10,000 Pa.
An ‘A’ rated AAV eliminates unsightly pipework in a bathroom, for example by allowing the stack to be terminated low down, which means that it’s not obstructing the living space and the aesthetics are improved.
The European Standard EN12380 was introduced in 2002 to establish requirements, test methods and evaluation of conformity for AAVs. Setting the industry benchmark for quality and fitness for purpose, a key aspect of the standard is Table 1, which details the rating system in relation to operating temperature range and installation position in relation to the flood level of the fixtures:
The ‘A’ rating ensures that, should a blockage occur within a building’s branch or stack pipework, the AAVs below the flood level of the fixture will function correctly. It is imperative to know that, for the lifetime of the product, the AAV will operate and there will be no compromise in performance – the last thing you want to be doing is greasing the AAV’s membrane, as advised by some manufacturers, for example, because the seal has become dysfunctional after 5 years – thereby exposing the fixtures and living space to potential flooding.
All Studor products are designed and manufactured to be maintenance free, which means they are an incredibly durable, sealed unit which will last for the lifetime of the system onto which they are installed.
A Guarantee of Quality
Marked on each Studor AAV you will see the ‘A’ rating in accordance with the EN12380 standard, which provides reassurance of quality and performance. In some markets it is rare to see an ‘A’ rating on an AAV product, as not all manufacturers are prepared to guarantee longevity and ongoing performance.
By contrast, the Studor product range has been rigorously tested to and above many industry standards (including, amongst others, Australia, Europe, UK and the USA). Our finely engineered membranes have been tested to open and close thousands of times, and across a diverse temperature range.
Our confidence in our quality is supported by our unique lifetime warranty, which means that we will guarantee tightness and functionality of our AAVs for the lifetime of the system onto which they are installed – visit here for full details.