Hi, 

Could you please advise. We own a mezzanine flat in end of terraced house 1930s house as a share of freehold with the downstairs flat. The house was converted into 2 private flats in about 1987, which are sharing small entrance lobby area (cca 1.5x1.5m). Both flats have the possibility of rear escape – downstairs flat directly into the garden. Upstairs flat through the escape window and across downstairs extension roof onto the garden/ alleyway. 

 Is there actually any relief on the FS requirements when having the option of rear escape ?

• Flat door must be FD30s – notional door upgraded with FR hinges, intumescent strips and door closer?
• Do No smoking and Fan simultaneous evac signs need to be installed in the lobby ?
• In the common lobby there is mains electrical cupboard for the upstairs flat- does this need to be 1 hr fire resistant enclosure (currently MDF)?
• Fire alarms currently battery operated grade F not interlinked. Can these be battery operated or must be hard wired? Does the common lobby smoke alarm need to be interlinked with the alarms inside both flats?
• Behind our flat entrance doors there is the staircase leading up into the flat. Does a heat/smoke detection need to be downstairs directly behind the flat entrance doors or upstairs in the flat circulation area, or both?

 Many thanks for any advise

This guide will help - p48 onwards for specific guidance. 

https://www.cieh.org/media/1244/guidance-on-fire-safety-provisions-for-certain-types-of-existing-housing.pdf

You will also require a written fire risk assessment.