Greetings all,
I have an unusual condition for a 3-level, mixed-use, fully-sprinkled building in California. I want to make sure I have the best code arguments before I meet with the building official.
The lowest level is subterranean parking, the middle level is office or retail, the upper level is residential.
Since the site is steeply sloping the upper residential area has its own driveway and parking on the "ceiling" of the mid-level and pedestrians can exit at grade to the sidewalk (Public Way).
The residential is only 3 units and the owner would prefer not to have the upper level and middle level not connected by a stair for security reasons.
This upper level design currently has only one exit path, down the concrete driveway (above the middle level).
Currently the common path of travel is too long to make it off the "building" to the public way with one exit (125' per CBC table 1006.2.1)
Approach:
I am thinking the residential driveway (above the retail/office) can function as an area of exit discharge. It is "sufficiently open to prevent the accumulation of smoke and toxic gasses.", ansd "provides a direct path of egress travel to grade"
So the individual freestanding residential units only have to "exit" to the driveway and this would satisfy the travel distance requirements for one exit.
The remaining item would be the fire rating of the driveway (floor/ceiling) to ensure a safe "exit discharge" above the Office/Retail use.
One is only required to have a 1-hour fire resistance rating between the carports (U) and the retail (M) below.
However, we could offer more. If it were 3-hr floor/ceiling assembly it would effective function as a horizontal building separation protecting the driveway area.
In my mind, this exit discharge ontop of a 20 foot plus wide driveway is safer than many exit discharges though a narrow courts or yards.
Any thoughts to support or contradict this approach.?
I have an unusual condition for a 3-level, mixed-use, fully-sprinkled building in California. I want to make sure I have the best code arguments before I meet with the building official.
The lowest level is subterranean parking, the middle level is office or retail, the upper level is residential.
Since the site is steeply sloping the upper residential area has its own driveway and parking on the "ceiling" of the mid-level and pedestrians can exit at grade to the sidewalk (Public Way).
The residential is only 3 units and the owner would prefer not to have the upper level and middle level not connected by a stair for security reasons.
This upper level design currently has only one exit path, down the concrete driveway (above the middle level).
Currently the common path of travel is too long to make it off the "building" to the public way with one exit (125' per CBC table 1006.2.1)
Approach:
I am thinking the residential driveway (above the retail/office) can function as an area of exit discharge. It is "sufficiently open to prevent the accumulation of smoke and toxic gasses.", ansd "provides a direct path of egress travel to grade"
So the individual freestanding residential units only have to "exit" to the driveway and this would satisfy the travel distance requirements for one exit.
The remaining item would be the fire rating of the driveway (floor/ceiling) to ensure a safe "exit discharge" above the Office/Retail use.
One is only required to have a 1-hour fire resistance rating between the carports (U) and the retail (M) below.
However, we could offer more. If it were 3-hr floor/ceiling assembly it would effective function as a horizontal building separation protecting the driveway area.
In my mind, this exit discharge ontop of a 20 foot plus wide driveway is safer than many exit discharges though a narrow courts or yards.
Any thoughts to support or contradict this approach.?
