Building regulations - means of escape, access rooms, automist and open plan

[salgw]

https://ibb.co/dr67z9
Hello,

Does anyone know where I can find information on when a hallway becomes an access room? Is there a specific measurement, or is it more about 'use' (ie if I put a table in a hallway, does it immediately become a room?).

My issue is I have an open plan kitchen at the moment, which was done by the previous owner of my flat. I've got a 3rd floor maisonette (so 3rd and 4th floor) of a purpose built block, where the stairs from upstairs empty into the kitchen. I've attached some plans for reference.

Although the external entrance to the flat is on the 3rd floor, with an external walkway, and you can escape from the upstairs windows to this walkway, our building control officer is saying that the installation of an automist system in the kitchen will not satisfy the regulation. Means of escape is still jeopardised and therefore I need to reinstate a wall in the kitchen. I don't see this as being very practical, so am looking into other options - including a fire curtain which would close off the kitchen in the case of a fire, and thereby creating a means of escape out of the flat. The BC officer has no experience with a mist system, and isn't really willing (or able it seems) to engage on the detail of the regulation or to be very helpful in any solution other than putting up a wall which has been removed for 15 years now.

Thanks and please ask any questions! This has been quite a struggle, and I'm getting to know some of the regulations quite well...

 

[Nakajo]

This is why I like to try to find an Approved Inspector who understands these systems. Presumably, the existing arrangement has been signed off at some point - at least to the satisfaction of the previous owner's insurers? So I can't see what the problem is.

 

[^woody^]

reinstate a wall

So the initial design is made worse, and you are effectively trying to come up with something as good but not actually designed as a whole system. This is different from designing a suitable system from scratch and will be viewed differently by the BCO.

Sprinklers or a mist system are not automatic compensatory alternatives. There are several factors to consider.

Smoke, hot or toxic smoke are a bigger threat than flame. Sprinklers can't always deal with this. Potentially, a suppression system in conjunction with enhanced early detection such as a L1 system may work, but it's not definitive.

The way people act in a fire, together with the layout may mean that a suppression system may not compensate adequately for a protected means of escape for a particular layout.

A properly designed and certified system by a qualified fire engineer may be able to demonstrate compliance to the BCO.

 

[lt8480]

If you flip the kitchen and living room around your lower floor is then fine as your living room isn't going through your kitchen (see 2.13b of Part B2, page 23).

For the upper floor they may accept the upper windows to be an alternative exit for Bed 2 (2.17 of Part B2, page 24). if you then separate the ground floor from the upper floor with fire separation this could also be used for Bed 1. This could be done with a fire door at the bottom of the stairs on a hold-open device so it just closes in the event of a fire system going off. You may also need to upgrade the stairs partition and floor separation depending on the existing fire ratings.

Overall this would be an improvement so would hope they would accept these changes.

My real thought is what are you doing that requires Building Control to be notified / signed off?

Were these changes agreed by the freeholder previously / was the flat show like this on your lease when you purchased? Anyway its beyond the enforcement period of 2 years I believe so not sure how they could force reinstatement unless you are making other layout changes surely?