Allowable # of Stories, Mixed Use, Non-separated, Type V-B

[classicT]

What say you? Can one have a mixed use, non-separated 'B' and 'S-1' building where-in the 'B' use is two stories?

Large open warehouse for storage with office space at one end that has an interior stairway to an open office area. 'B' use is not open to the warehouse , but the separation wall is non-rated.

Can the 'B' be two stories even though the 'S-1' is limited to one story?

508.3.2 Allowable Building Area and Height
The allowable building area and height of the building or portion thereof shall be based on the most restrictive allowances for the occupancy groups under consideration for the type of construction of the building in accordance with Section 503.1.

504.2 Mixed Occupancy
In a building containing mixed occupancies in accordance with Section 508, no individual occupancy shall exceed the height and number of story limits specified in this section for the applicable occupancies.​

 

[RLGA]

You can, provided the 2nd story Group B is separated from the Group S-1 with fire barriers and a horizontal assembly per Table 508.4. The Group S-1 and Group B on the 1st story could be un separated, but the supporting construction for the 2nd story’s separation would also need to be fire-rated. Therefore, it is probably best just to provide a fire barrier between the Group S-1 and Group B (both stories). In this case, you would base your allowable area on the separated occupancies method.

 

[classicT]

You can, provided the 2nd story Group B is separated from the Group S-1 with fire barriers and a horizontal assembly per Table 508.4. The Group S-1 and Group B on the 1st story could be un separated, but the supporting construction for the 2nd story’s separation would also need to be fire-rated. Therefore, it is probably best just to provide a fire barrier between the Group S-1 and Group B (both stories). In this case, you would base your allowable area on the separated occupancies method.

Agreed.

I actually indicated sprinklers as another viable option (sister building being built next door on the same lot has them). Design professional is indicating that 508.3.2 does not specify allowable number of stories, thus the proposed is ok. It was my comment during plan review, that the 2nd story (even though it is a B), is not permitted in a Type V-B building that has a S-1 mixed use w/out sprinklers.

 

[steveray]

Mezzanine?

 

[classicT]

Mezzanine?

Nope... single stair, not open to level below, etc.