Stairs to Basement

[Del777il]

What does it mean when ADB reccimends that in a single staircase building the staircase should not carry down to the basement rather terminate at Ground level and separate staircase follow down to the basement. Does it mean the basement staircase should be accessed from outside the building or can it be accessed from a door at ground level within the main staircase.

 

Thank you.

[Tom Sutton]

It can be accessed from a FD30s fire door at ground level within the main staircase and a second FD30s fire door at basement level or a FD60s fire door at ground level within the main staircase. It also could be accessed outside providing a minimum 60 minutes fire separation between the basement and ground floor.

[Del777il]

Thanks Tom I appreciate the response. In the case where the natural vented smoke shaft continues to the basement lobby, is a vent at the head of the basement stairs also required as would normally be provided for upper floors as per para 2.26 ADB ? I cannot see how this could be feasabily provided.

[Tom Sutton]

I need more information like the type of premises and the size.

[Guest GThorn]

Hi Does this mean that a basement fire escape staircase does not need a set of doors at the bottom of the stairs, if it leads to a final protected exit, with a separation of one hour. ? The premises in question is a restaurant at basement level and ground floor level with approx 40 covers in basement and 80 covers on ground floor.

[Tom Sutton]

On 27/05/2021 at 16:57, Guest GThorn said:

Hi Does this mean that a basement fire escape staircase does not need a set of doors at the bottom of the stairs, if it leads to a final protected exit, with a separation of one hour. ? The premises in question is a restaurant at basement level and ground floor level with approx 40 covers in basement and 80 covers on ground floor.

It sounds that your description would achieve the one hour separation between the ground floor and the basement but without seeing it I cannot be a 100% certain.

[Tom Sutton]

On 15/03/2020 at 19:25, Del777il said:

Thanks Tom I appreciate the response. In the case where the natural vented smoke shaft continues to the basement lobby, is a vent at the head of the basement stairs also required as would normally be provided for upper floors as per para 2.26 ADB ? I cannot see how this could be feasabily provided.

Are you using the current 2020 ADB?