Protection of exit discharge

[pmarx]

This is under the 2006 IBC. I'm asking this as a designer, not a code official. The office I'm in "inherited" this project from another architect and some buildings have already been reviewed and are under construction. An 3-Story, R2, two bedroom, Type 5A stucture. NFPA 13R supression. The dwelling units do not share common exits...everyone has their own front door. Some of these front doors are facing each other within what is essentially a breezeway, namely an exterior space under the upper level floors and open at each end. An occupant can therefore exit their unit and turn left or right to travel on to "a street or public way". The minimum width of this breezway is 6 ft. The exterior walls and floor/ceiling assembly above are rated for 1 hour and these front doors are rated for 45 min. As I stated above, some of these buildings (which vary from 10, 15, 20 and 25 unit configurations) have already been given permits and are under construction. what hasn't been reviewed yet (but I believe has been discussed with the authority having jurisdiction) is that in a handful of these ground floor units have a third bedroom with a single 2x3 nom. unprotected window facing into this common breezeway. This is at only one end of the breezeway. This is one of those rare occassions where I think everyone else is being too liberal. Because the occupants are not at a street or public way when they walk out of their front doors but have to continue for a distance of 20-30 ft depending on if they turn left or right, I think this breezway serves the function of an egress court (1024.5). Does the fact that going past that opening isn't an occupant's only choice have anything to do with it being unprotected? Sorry this was so long and I hope I made myself clear.

View attachment 1400

_Bldg 900 - A2.1 A-2.pdf

_Bldg 900 - A2.1 A-2.pdf

 

[Builder Bob]

Is the window located under the overhang of the roof above, if it is, I would consider the "corridor" wall not to be protected to the point of exit discharge.....Just My $.02 cents worth..... Relocate the window beyond the edge of the roof overhang above, it is "outside" the building. ( Be sure to look at definitions for building area, fire area, etc.)

 

[Yikes]

pmarx - just to clarify - this "breezeway" has occupied space or a roof covering over all of it, and it is NOT open to the sky, correct?

If it is NOT open to the sky above with an unobstructed width (view to the sky) of at least 44" (1024.5.1) from the window location to the public way, and if this is the only exterior opening from the third bedroom, then you have a problem per 1026.1: a "court" must be unobstructed to the sky per the IBC 202 definition.

Nor would such a space qualify as an atrium per 1026.1 exception #1, unless it connected 2 or more stories (404.1.1).

If it IS open to the sky, you will still need 45 minute protection per 1024.5.2, unless the occupant load going past htie window is less than 10 (exc. #1). some jusrisdictions allow a water curtain to function as an alternative means of protection ( see http://ladbs.org/LADBSWeb/LADBS_Forms/PlanCheck/PC-STR.Mod49-SprinklersatEgressCourt.pdf ).

Lastly, if your 2x3 bedroom window is anything other than a casement, you'll probably have an emergency escape issue per 1026.2.1.

 

[pmarx]

Bob & Yikes, thank you for your replies.

Is the window located under the overhang of the roof above

Not the roof, but the 2nd and 3rd floors. The the "north" of the two column forms/broken lines there is just sky above. To the "south" you are under the upper floors.

Relocate the window beyond the edge of the roof overhang above, it is "outside" the building

That isn't possible as the window wouldn't be within that bedroom

just to clarify - this "breezeway" has occupied space or a roof covering over all of it, and it is NOT open to the sky, correct?

Correct

you have a problem per 1026.1: a "court" must be unobstructed to the sky per the IBC 202 definition.

Technically yes and perhaps my use of the term "egress court" was incorrect. Fig. 1024.5 of the 2006 commentary was a close to the configuration I'm dealing with.

Lastly, if your 2x3 bedroom window is anything other than a casement, you'll probably have an emergency escape issue per 1026.2.1.

I believe we comply with exception 1 of 1026.1

An 3-Story, R2, two bedroom, Type 5A stucture. NFPA 13R supression.

As I said, these plans have previously been reviewed and released and the local AHJ hasn't brought this up. I'm the one who thinks the window needs a min. 3/4 hour rating.

 

[Yikes]

I just meant that if your bedroom window doesn't actually open up to provide at least a 20" wide x 24" tall clear escape route, then you have another problem - - though not the problem you originally posted about.

In my experience with a 2'x3' bedroom window, a horizontal slider of single-hung window of this size won't provide a large enough opening per the measurements listed in 1026.2.1 - - only a casement window could work. The exception #1 in 1026.1 does not address this size issue.

Again, this is a sidetrack to the original question.

 

[Builder Bob]

I would agree that the window would need to be 45 min protection ------ The point that I was trying to make is that if a floor or roof is located above, it is technically considered to be inside the building ----- Don't let this be confused with a thermal envelope of the building......

 

[JBI]

What's the problem with changing the window out for fire protection rated glazing? it's only one window per unit and not all units have one...

 

[Yankee]

What's the problem with changing the window out for fire protection rated glazing? it's only one window per unit and not all units have one...

Cha-chinggggg

 

[pmarx]

What's the problem with changing the window out for fire protection rated glazing? it's only one window per unit and not all units have one...

There's really no problem (yet) because this isn't an issue with the AHJ. I just thought this was something that was "missed".

I just meant that if your bedroom window doesn't actually open up to provide at least a 20" wide x 24" tall clear escape route, then you have another problem - - though not the problem you originally posted about.

I understand that there could be a problem but isn't because of the sprinkler exception.

The point that I was trying to make is that if a floor or roof is located above, it is technically considered to be inside the building

Well now you have me thinking in another direction. If that is the case then I define this breezeway as part of the exit access, not the exit discharge because it serves more as a corridor (that gets real cold in the winter). I still think the window would be required to be a protected opening but only for 20 min.