Hockey_guy
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I am trying to determine if altering this building is going to create some kind of limits on occupancy. Some of the divisions on the second floor are being altered to create more but smaller office suites. The building is 100 years old, 2900ft2 single stair building with multiple B (office) suites on the second floor, and multiple M (retail stores) on the first floor. The single staircase is 48" wide. Location is Upstate NY.
Under the 2020 Existing Building Code of NY if using work area compliance method:
805.3.1.1 Single-exit buildings allows single exit for B occupancies for not more than two stories, and not greater than 3500ft2 per floor.
805.4.1.1 Requires a second exit for rooms and spaces with occupant loads greater than 50, Except for the single-exit buildings above.
So the Existing building code allows this occupancy group and does not have much to say about putting / changing occupancy limits on these single stair buildings. Existing building code intended to be less strict than code for new construction.
Under the 2020 Building Code of NY
1005.3.1 Means of egress sizing of 0.3 inch per occupant means the 48" staircase would be sized for 160 people.
1006.2.1 Maximum occupant load of 49 ((per space)) with one exit
1006.3.3(2) allows B on a single stair second story, and gives a maximum occupant load of 29 for the entire story.
Or is all of this a non-issue since occupancy limits are not required to be posted for B (and an A less than 50 which becomes a B)?
I want to put in a second staircase to the rear but there is not quite enough room to fit one that is compliant with current code for steepness and for distance from the main staircase. I can fit a steeper second staircase. Understanding what is permissible with the single stair might help the AHJ to approve the steeper second staircase. Or maybe keep it as a single stair building on paper with a "utility" staircase in the back.
Thank you all for your ideas.
Under the 2020 Existing Building Code of NY if using work area compliance method:
805.3.1.1 Single-exit buildings allows single exit for B occupancies for not more than two stories, and not greater than 3500ft2 per floor.
805.4.1.1 Requires a second exit for rooms and spaces with occupant loads greater than 50, Except for the single-exit buildings above.
So the Existing building code allows this occupancy group and does not have much to say about putting / changing occupancy limits on these single stair buildings. Existing building code intended to be less strict than code for new construction.
Under the 2020 Building Code of NY
1005.3.1 Means of egress sizing of 0.3 inch per occupant means the 48" staircase would be sized for 160 people.
1006.2.1 Maximum occupant load of 49 ((per space)) with one exit
1006.3.3(2) allows B on a single stair second story, and gives a maximum occupant load of 29 for the entire story.
Or is all of this a non-issue since occupancy limits are not required to be posted for B (and an A less than 50 which becomes a B)?
I want to put in a second staircase to the rear but there is not quite enough room to fit one that is compliant with current code for steepness and for distance from the main staircase. I can fit a steeper second staircase. Understanding what is permissible with the single stair might help the AHJ to approve the steeper second staircase. Or maybe keep it as a single stair building on paper with a "utility" staircase in the back.
Thank you all for your ideas.
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