Protected stair access

[Lyledunn]

I am converting the ground floor of an existing 4-storey office building to restaurant use. The ground floor will be let out. 60min fire protection is required between occupancies. Now a protected stair serves the upper floors which remain as office accommodation. D2 will provide an alternative means of escape from the restaurant. I am of the view that the wall separating the restaurant and the protected stair should be 60min and D2 should only be used for MOE and not used for any other purpose. I could see deliveries coming in from the yard area where there is a large open car park. Knowing restaurants as I do, I could see D2 propped open, damaged, with loss of integrity in a short time. BC hasn't raised any concern about the issue and the developer is howling in protest at my suggestion of a functional door for the kitchen. I dont feel comfortable and may withdraw as designer until a fire engineer reports. Would appreciate comment.

[Mike North]

I must agree, door D2 will be beaten black and blue with deliveries been transported through it.  I would also suggest that D2 and the external door to the yard will also be propped open to allow cross ventilation of the kitchen. Have you thought about a free swing closer which may cure the issue

[Lyledunn]

Many thanks Mike.

If I assess the situation correctly, from a building regulation perspective, because of the different occupancies, the first floor should be a compartment floor and thus the protected stair should be in a 60min shaft. Consequently, D2 should only be used as a MOE. When I made the BC submission, I was expecting rejection of the proposal on that issue. That would have made life simpler for me as the client would have no option but to comply. As it stands, it is a design issue over which the client feels he can exercise discretion. If BC say its ok by not referring to it, then it must be ok to ignore advise from the designer. That, unfortunately, is how many clients see things. 

However, irrespective of BC input, I, as the designer, have a clear responsibility, both under fire safety law and CDM. I intend to exercise my responsibility to ensure that the risk is ALARP.

 

[Lyledunn]

On 25/07/2024 at 07:31, Mike North said:

Have you thought about a free swing closer which may cure the issue

Come to think of it, I don’t believe I have seen a free swing device on a door to a protected stair. Although I would be uncomfortable with such a situation, I don’t see anything that says it shouldn’t be done, and, as you say, it would be better than the bashing the door is likely to get if fitted with a standard self-closer. 
However, the primary objective in any design is to either remove the hazard or introduce control measures to reduce the risk, the former being preferred. Cutting a new door into the kitchen from the yard would meet the concept of the former.

[Mike North]

You could always form a new opening between the yard and kitchen which would probably need not be a fire door