As part of an extensive refurbishment programme, Stonbury have been replacing the push-fit vents used inside security access covers on reservoir roofs. The vents allow air to pass through the reservoir while preventing insects, small animals and debris from entering the tank.

The standard replacement vent relies on a rubber surround to hold the mesh in place and to remain wedged within the apertures of an access cover. However, we have found the push-fit vent to be extremely unreliable, often finding them loose, or in some cases to have fallen out completely.

The push-fit vents are single-use items which deteriorate over time and require complete replacement. This can be both costly and time-consuming as we have also found the push-fit vents to be very awkward during installation.

With all of this in mind, several members of our team worked together to find an alternative solution to the push-fit vent, that would;

  • Guarantee a secure and firm fit
  • Reduce installation time
  • Be re-useable

Several alternative solutions were discussed, including; the use of a sealant to secure the vents into place and steel frames which could be screwed onto the cover.

However, the sealant did not adhere to the rubber surround very well, was particularly messy and took a lot more time to complete. The screw-in vents were also ruled out as they required drill holes which would invalidate the manufacturers guarantee on the covers.

Following further discussions and the development of a prototype, the team agreed the best solution was a stainless-steel magnetic vent.


  • The vent is slightly larger than the standard push-fit vent, offering a higher volume of airflow
  • The design can be used with both stainless-steel and nylon mesh, making it suitable for assets with high
    chlorine levels
  • There is opportunity for bespoke designs to suit different hatches
  • The design can be adapted to cover multiple apertures
  • The vent is simple to remove, although does require adequate force due to the strength of the magnets
  • The vent is very easy to maintain and wipe clean where debris has built up
  • The powerful magnets will not be affected by air pressure or blockages, keeping the vents securely in
    place at all times
  • The vent can be re-used by simply replacing the mesh when required
  • The magnets will not cause adverse effects to any of the alarm instrumentation

For more information on the Stonbury magnetic vent design, please get in touch -

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