Mr

[Guest James]

Hello,

I live in a flat in a former 1960s or 1970s post office building that was converted into flats in 2014.

It's a Waitrose mini supermarket on the ground floor and the 1st, 2nd and 3rd floors contain 11 flats in total (quite high spec with a lift and very thick and solid doors which I suspect are 1 hour fire doors as not much sound gets through).

It has an addressable fire alarm system that covers the communal areas (I don't think it's linked to Waitrose) but no Grade A detection or sounders in the 11 flats.

A fire risk assessor has said that a Grade A combined heat detector with sounder is required in the hallway of each flat and the sounder must reach 75dB in each bedroom.

My question is that, surely, the conversion must have met the building regs that were required of it in 2014 for it to be signed off?

Assuming it did meet the building regs, is the fire risk assessor correct as it was only 8 years ago?

Thanks,

James

[AnthonyB]

If the build was to the recommendations of Approved Document B and adopts a stay put approach based on:

- 60 minutes fire separation between shop & flats, flats and common space and between each flat

- Smoke control system to stairs & lobbies

then it needs no common alarm system beyond a silent detection system to open smoke vents and thus nothing in flats other than their local domestic systems.

If the conversion was not to Approved Document B (as a deliberate design decision or in error), omitting one or more of the above (or some of the other ADB recommendations) then a simultaneous evacuation approach  may be necessary and this requires an audible common system that, to alert flat occupants even when asleep, requires a sounder and detector from it inside each flat. Whilst on paper it should be 75dB bedhead in practice it's almost universally accepted for the domestic standard to be used of 85dB at the bedroom door so normal size and layout flats only require a heat detector and sounder base to the flat's internal hallway.

Building Regs sign off is almost universally accepted as being meaningless from a fire safety point of view due to how often incorrect or defective builds get through the system (Grenfell being the worst example) so if the actual situation is non compliant and unsafe so as not to meet fire regulations then any competent assessor will flag it for action.

So they could be right.....but without seeing the site I couldn't be sure.

[Guest James]

On 12/09/2022 at 20:15, AnthonyB said:

If the build was to the recommendations of Approved Document B and adopts a stay put approach based on:

- 60 minutes fire separation between shop & flats, flats and common space and between each flat

- Smoke control system to stairs & lobbies

then it needs no common alarm system beyond a silent detection system to open smoke vents and thus nothing in flats other than their local domestic systems.

If the conversion was not to Approved Document B (as a deliberate design decision or in error), omitting one or more of the above (or some of the other ADB recommendations) then a simultaneous evacuation approach  may be necessary and this requires an audible common system that, to alert flat occupants even when asleep, requires a sounder and detector from it inside each flat. Whilst on paper it should be 75dB bedhead in practice it's almost universally accepted for the domestic standard to be used of 85dB at the bedroom door so normal size and layout flats only require a heat detector and sounder base to the flat's internal hallway.

Building Regs sign off is almost universally accepted as being meaningless from a fire safety point of view due to how often incorrect or defective builds get through the system (Grenfell being the worst example) so if the actual situation is non compliant and unsafe so as not to meet fire regulations then any competent assessor will flag it for action.

So they could be right.....but without seeing the site I couldn't be sure.

Thanks for your excellent reply Anthony, very helpful.

I've discovered that there was a stay put policy in place until the fire risk assessor couldn't ascertain whether the compartmentation between floors was sufficient. The floors are concrete so the issue was whether fire could spread through pipes, voids etc between floors.

I don't know how that can be ascertained either

[Tom Sutton]

Not a very good fire risk assessor then.

[AnthonyB]

On 14/09/2022 at 15:18, Guest James said:

Thanks for your excellent reply Anthony, very helpful.

I've discovered that there was a stay put policy in place until the fire risk assessor couldn't ascertain whether the compartmentation between floors was sufficient. The floors are concrete so the issue was whether fire could spread through pipes, voids etc between floors.

I don't know how that can be ascertained either

Compartmentation survey by a specialist company - although some would be obvious and easy to check if the assessor actually tried to look.