A commonly asked question is whether Air Admittance Valves (AAVs) can be installed outside. In the UK Part H of the Building Regulations 2010 (clause 1.33) states that “Air admittance valves should not be used outside buildings…” Reasons for this include:
As Part H of the Building Regulations 2010 does not approve external use, a specific third party approval (such as the BBA) is required.
Any AAV marketed for external use must be supported accordingly with an approval which specifically states that that specific model of the product may be installed outside.
If the third party certificate doesn’t list the specific model, and doesn’t specifically state for “external” or “outside” use, then it’s not Part H compliant and installing it would risk rejection by Building Control.
The Studor Maxi-Vent, however, is uniquely certified by the BBA as being approved for both internal AND external installation. This means that the Maxi-Vent Air Admittance Valve (AAV) may be legally installed outside in the UK when installed in conjunction with the Aluminium Cover, and the BBA approval will satisfy Building Control that the installation is Part H compliant.
Whilst the BBA approval for external installation of the Studor Maxi-Vent was granted in 2013, Studor has been selling the Maxi-Vent for outside installation (in conjunction with the Aluminium Cover) worldwide since 2003 – over 14 years ago!
AI rated (-20°C to +60°C) in accordance with European Standard EN12380, without the insulating cap or Aluminium Cover, the Maxi-Vent is actually independently verified to operate right down to -40°C!
For added protection against UV degradation, the Maxi-Vent is manufactured with a UV stabiliser, and its design incorporates internal and external screening as a barrier to the ingress of debris, animals, insects and birds. The Aluminium Cover may even be painted to match surrounding pipework or brickwork if required.
Maintenance free, and provided with Studor’s standard 10 year warranty, the Maxi-Vent really is the only choice for an external AAV – not only does it uniquely have the required approval for legal installation of an AAV outside, but it is also specifically designed to be robust enough to be installed externally – ticking all the boxes!
Before: Vent pipe through roof
After: Maxi-Vent with Alu Cover
Alu Cover painted to match surrounding pipework