AnthonyB

Independent tests by the Building Research Establishment indicate a typical 25 year life (varying by type of device) for detectors and it would be unwise to exceed this although, as long as the devices function during service tests & aren't causing false alarms, there is nothing to make this mandatory. 10 years, often stated by maintenance firms, is purely the warranty period of some manufacturers.

Would the door ever feasibly be locked when someone was inside, requiring the key to escape? If so then really it should be a thumb turn.

Find a new BCO! How many floors is it and what's the planned layout - these are the usual triggers for sprinklers in a single dwelling under Building Regulations. https://assets.publishing.service.gov.uk/media/639ae7e98fa8f5069839c7d7/Approved_Document_B__fire_safety__volume_1_-_Dwellings__2019_edition_incorporating_2020_and_2022_amendments.pdf The Fire Safety (England) Regulations are outside their jurisdiction, won't apply once a single dwelling and even whilst still flats have limited practical scope whist vacant and certainly have nothing to do with requiring sprinklers/mist https://www.gov.uk/government/publications/fire-safety-england-regulations-2022

How many floors? The appropriate guidance is here http://www.cieh.org/library/Knowledge/Housing/National_fire_safety_guidance_08.pdf

The fire risk assessment you have to carry out (you are responsible for legal compliance of the office whilst leasing it and employing people there, not your landlord) would not only address fire risks and required precautions in your office but also the effect of a fire in your office on the flats above. From your description it sounds like this has been looked at in the past and the fire separation deemed inadequate hence why the fire alarm in your unit is also covering the flats. In theory as the system controls and power are in your demise they are under your control for maintenance - this is the default fire safety law position - however this can be overruled by contract law - if your lease includes a service charge and that the fire alarm system in common is a service charge item then the landlord should be maintaining it. There is a legal requirement for cooperation between different Responsible Persons (which can include the landlord where they retain control over an aspect of the building) so your landlord may be breaking the law. If you have fire safety concerns then you should contact the fire service Business Fire Safety Team. If you have landlord/tenant/lease related issues you should contact an appropriate lawyer.

In a block that small 30 minutes fire resistance is usually acceptable which it sounds like it has (notional 30 minutes can be achieved by lath & plaster under timber so asbestos under timber would be better). A small shared lobby wouldn't need to have smoke control and the only requirement would be that the flat front doors were fire doors to the standard applicable at the time of conversion. Stay put would usually be acceptable, no common alarms needed. If there is a stair and landings in common it may be needed to apply the guidance used in your FRA but that only applies where the conversion doesn't give the same standard as a post 1991 build - it's possible in the smallest blocks that were converted before 1991 to still meet the standards that were introduced then. If a common alarm is required then yes it must be mains powered. Residential risk assessment is highly specialised with each case determined on it's merits and whilst there are general trends based on a properties age they aren't hard and fast.

It's nothing to do with Building Regulations which wouldn't apply to an existing building not undergoing alterations - it's a fire safety legislation issue A proper Fire Risk Assessment will determine to what standard the doors need to be - depending on the size and layout of the block older standard fire doors are fully acceptable if still in working condition. The amended Fire Safety Order includes flat front doors, windows and external structure as the responsibility of the freeholder or RMC to assess and ensure are adequate for the risk. Doors that aren't to the appropriate standard must be remediated, usually at the cost of the flat in questions owner and the freeholder/TMC is expected to ensure this is done with an expectation for them to resort to civil legal action or enforcement action via the local authority if needed.

Are they, presumably being new boards, in a non combustible housing, i.e. all metal? They certainly aren't a defined area of special fire hazard.

No, it's not retrospective - as long as it is in safe, efficient working order you are fine.

It's your house, you can do as you wish, you aren't required to.

If the tamper seal on the safety pin is intact then you should be OK. Of course as you should be having these serviced annually the service engineer would have checked this for you. If you are really worried get it serviced again early or weigh it. If it's more than 10 years old it needs other corrective action anyway.

As the Council are the enforcement body then if they are happy with good fitting solid doors to bedrooms and only a fire door to the kitchen then that's all you need to do - this sounds like a Housing Act HHSRS issue so different guidance applies compared to if you were carrying out work under Building Regulations

It's all in BS7273-4 and yes the link should be local to each door.

Live plants? With two escapes and a managed use policy then in theory - however they would need regular watering and care as if they die of and dry out they would be a hazard and would likely fall below the required fire performance for a circulation area of Class 0/Euro Class B-s3,d2 if treated as a wall lining.

The risk assessor is correct and reflects the Government guidance that sets out requirements in small premises - domestic smoke alarms are for homes not places of work: https://www.gov.uk/government/publications/making-your-small-non-domestic-premises-safe-from-fire Means of giving warning in the event of a fire In single storey premises with open plan layouts and small numbers of people, the alarm could be raised by shouting ‘fire’. Alternatively, the alarm could be raised manually, using a hand-operated bell or siren. In premises of more than one storey, where the above method of giving warning would be unreliable, an electrical fire alarm system should be installed. These systems should have ‘break glass’ call points and fire alarm sounders, connected to a control panel. In premises of more than one storey, where a fire might start and be undetected in its early stages, the fire alarm system might need to incorporate automatic fire detectors. These will generally be smoke detectors or, in the case of kitchens or other rooms in which smoke detectors would cause false alarms, heat detectors).