Elevators and smoke control in corridors

[nealderidder]

I don't know how many times I've done this... can't seem to keep it straight in my head.

4 story building, 1st floor is A & B occupancy. 2nd through 4th are R-2. I'm not required to have elevator lobbies per 707.14.1.4

At 1st floor, corridors are not required to be rated, thus I don't need to worry about a smoke seal at the elevator door(s).

Above the 1st floor in the R-2 my sprinklers don't get me out of the requirement for rated corridors (including smoke control per 715.4.3.1 in 2006).

So... I could omit any lobby or smoke doors on the 1st floor assuming the elevator doors are fire rated appropriately for the shaft.

But.... On the upper floors I need some way to control smoke in the corridor. This would mean an automatic something or other over the elevator doors that prevents smoke transfer or build that lobby I'm trying to avoid and use doors with smoke seals on mags to meet the requirement for smoke control.

Do I have this right?

Thanks,

Neal

 

[texasbo]

You're pretty much there, although the smoke control isn't necessarilly what's driving the lobbies/seals at the upper floors; you can use pressure manipulation to get around that. The corridor rating is what's requiring the lobbies/assemblies for elevator openings on 2-4.

 

[permitguy]

A pitfall to avoid: do you need the elevator as an accessible means of egress? If so, you need lobbies or horizontal exits in the '06 (See 1007.1, 1007.2, 1007.4).

This changed in the '09 and '12, where the lobby/horizontal exit isn't required for an elevator being used as an accessible means of egress in a fully sprinklered building (1007.4 Exception 2). Side-hinged swinging doors on mags (tied to elevator SDs) which close over the elevator openings will provide the corridor opening protection.

If necessary, you could see how the AHJ would feel about using the '09 or the '12 as an alternative method.