The property comprised two 2-story houses which had previously been converted into flats. A new developer had constructed a further flat in the roof space of each house and this had created a means of escape problem with the extension of the two-storey escape stair. I was commissioned to find a remedy. Each roof top flat had a self contained hard wired smoke and heat detection system. The new roof top flats were served by an extension of the existing staircase. The staircase had been fitted with a hard-wired interlinked smoke detection system, employing a smoke detector outside each flat’s front door. The developer felt he had done all within his power to provide a suitable package of active and passive fire precautions, bearing in mind he had no right of access to upgrade the doors in the occupied flats.
After surveying the building and considering the great difficulty of upgrading the internal doors to FD 20S of the occupied flats required under the current code (some doors were glazed and seen as characterful by the residents) the function of the non-fire resisting internal doors was carefully reviewed.
The solution to the problem was to leave the internal doors as they were, increase the fire resistance and smoke resistance of the front doors of the existing flats to prevent a fully developed fire invading the staircase, and install a sounder (not a detector) just inside the front door of each occupied flat giving minimum disruption to tenants, the sounder forming part of the staircase fire detection system so that smoke in the staircase would be brought to the attention of everybody in the flats giving them time to escape. This was accepted by building control.
Client: private developerShare