AOV (Automatic Opening Vent)

Following the tragic fire at Grenfell Tower block there has been a concerted effort to ensure all tower blocks have improved fire protection and escape methods to ensure the safe evacuation of people should a fire occur.

These systems include the upgrade or introduction of sprinkler systems, fire detection / alarms systems and the installation of AOV (Automatic Opening Vents) in stairwells to aid the removal of smoke whilst the stairwells are being used to evacuate people. The AOV opening would then have a automatically controlled cover fitted which when the fire alarm system activated would open allowing smoke building in the stairwell to escape.

Drill Masters were contracted by EPS Fire and Security to form a 1.3m x 0.8m opening in the reinforced concrete roof of the 16 storey tower block, St Francis Tower in Ipswich. As there was no handrail on the roof area of the tower block a specialist scaffolding company were employed to provide a secure work area for the cutting to commence. This was supported with a crash deck below the opening to ensure no debris or people could fall through the opening whilst it was being constructed.

Due to the difficult access to the roof area and space constraints Drill Masters employed hydraulic diamond cutting equipment to cut through the 650mm total thickness roof. The roof was made up of a stone covering followed by a felt layer then 100mm block insulation on top of a 300mm thick ply based sheet and polystyrene insulation sandwich all on top of a 300mm thick reinforced concrete slab.

AOV opening

All the layers were divided into small cubes to enable the safe removal from the roof via the staircase. Once the 1.3m x 0.8m opening had been formed specialist roofing contractors ensured the area was fully watertight with new surround installed. In total the project from Drill Masters perspective took 3 days to complete with extra time required to lower all the debris from the 16th floor to the ground floor and disposal in the site skips.

The team at Drill Masters are seeing a greater requirement to form AOV or Smoke Vent openings in reinforced concrete roof structures in tower blocks as a direct result of the tragic fire at Grenfell.

Drill Masters are expert Diamond Coring and Concrete Cutting specialists and can assist with any diamond drilling, floor sawing or concrete removal project within Cambridgeshire, Essex, Suffolk and Norfolk. Contact us here for assistance. For more information on our range of diamond coring services and how we can help your project visit the services section of our website.