Options for smoke control at hoistway doors

[nealderidder]

I've got a two-story "B" use over two stories of underground parking garage "S-2". This is in CA, 2019 CBC.

Elevator lobbies are not required (no AMOE elevator, not high-rise, no area of refuge needed, no fire access elevator req'd) and I'm fully sprinkled. So I don't need lobbies but I do need smoke control.

The owner does not want to provide lobbies, nor secondary hoistway doors, nor pressurization. So I'm stuck with some sort of smoke control at the hoistway doors. In CA this is specifically addressed in 3006.3 #5 (smoke containment per ICC ES AC 77).

First question - are my assumptions above correct? Am I missing anything that would preclude the need for a "smoke curtain" at the hoistway doors?

Second question - do you now of an elegant solution to this? I've seen a few where the coiled curtain housing can sit above the ceiling and drops down when activated but they had ugly guide-rails that had to be installed. Something that looks like a smoke curtain scabbed on to the hoistway is not gong to be OK with this client.

Any ideas/recommendations would be appreciated!

 

[cda]

Not a building code person

Are the two undergrounds a story??



STORY. That portion of a building included between the upper surface of a floor and the upper surface of the floor or roof next above (see "Basement," "Building height," "Grade plane" and "Mezzanine"). A story is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceiling joists or, where there is not a ceiling, to the top of the roof rafters.

[DSA-AC] That portion of a building or facility designed for human occupancy included between the upper surface of a floor and upper surface of the floor or roof next above. A story containing one or more mezzanines has more than one floor level. If the finished floor level directly above a basement or unused under-floor space is more than six feet (1829 mm) above grade for more than 50 percent of the total perimeter or is more than 12 feet (3658 mm) above grade at any point, the basement or unused under-floor space shall be considered as a story.

 

[cda]

Use a door? And door holder?

 

[classicT]

Here are some picture examples. 2-curtain examples, and 1-door example

 

[steveray]

I saw those curtain ones in a class and seemed like a good solution....

 

[cda]

I hate curtains

Never seem to work

 

[nealderidder]

Not a building code person

Are the two undergrounds a story??



STORY. That portion of a building included between the upper surface of a floor and the upper surface of the floor or roof next above (see "Basement," "Building height," "Grade plane" and "Mezzanine"). A story is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceiling joists or, where there is not a ceiling, to the top of the roof rafters.

[DSA-AC] That portion of a building or facility designed for human occupancy included between the upper surface of a floor and upper surface of the floor or roof next above. A story containing one or more mezzanines has more than one floor level. If the finished floor level directly above a basement or unused under-floor space is more than six feet (1829 mm) above grade for more than 50 percent of the total perimeter or is more than 12 feet (3658 mm) above grade at any point, the basement or unused under-floor space shall be considered as a story.

The two parking levels are not "stories" if we're talking about allowable building height but I don't think that applies when we're talking about height of an elevator shaft?

 

[nealderidder]

Here are some picture examples. 2-curtain examples, and 1-door example

View attachment 7558
View attachment 7560
View attachment 7559

They aren't pretty when deployed but I'm leaning toward the middle photo above. I believe those are magnetic and run down the face of the elevator frame with no extra rails. If you drop a soffit above the doors you don't have rail "extensions" that run above the elevator door and look out of place. Seems like the most "invisible" option.

 

[nealderidder]

Use a door? And door holder?

An option but I'm hoping to avoid that.

 

[classicT]

They aren't pretty when deployed

Uhm... they deploy when there is a fire. Do you need the building to be "pretty" while it burns?

 

[nealderidder]

Uhm... they deploy when there is a fire. Do you need the building to be "pretty" while it burns?

Ha! No. I was saying they aren't pretty in the photo but you never really see them in that position anyway