Fire House sleeping quarters: dwelling Unit or sleeping Unit

[Tim Mailloux]

Doing an internal code review for a large public safety facility (police and fire), type IIb construction, non-separated mixed use B, R-2 and S-2. The 2nd floor of the facility contains an R-2 suite for the fire fighters that include 5 bedrooms, shared toilet and bathing facilities, a full kitchen with cooking appliances, and a common day room. The designers assertion is that this suite is a dwelling unit, and that only the perimeter walls around the dwelling unit need to be fire rated and the individual bedrooms do not require a fire rating as they are not sleeping units. By definition, the arrangement of this suite and the amenities included is a text book dwelling unit. My counter argument playing devils advocate is that while the fire fighters sleep and hang out in this space when on duty, no one lives there and dwelling unit to me implies permanent residency. What are your thoughts? Can this suite be treated as a dwelling unit, or should all the individual bedrooms be treated as sleeping units which by code would require that each bedroom be rated.

 

[ICE]

California Building Code.....which might be different than the code you are under with this project. In California the answer is dwelling unit.

DWELLING UNIT. A single unit providing complete, independent living facilities for one or more persons, including permanent provisions for living, sleeping, eating, cooking and sanitation.

SLEEPING UNIT. A single unit that provides rooms or spaces for one or more persons, includes permanent provisions for sleeping and can include provisions for living, eating and either sanitation or kitchen facilities but not both. Such rooms and spaces that are also part of a dwelling unit are not sleeping units.

 

[RLGA]

No time limit is associated with the definitions of dwelling unit and sleeping unit.

 

[TheCommish]

if it is a type IIb construction, non-separated mixed use B, R-2 and S-2, would the most restrictive requirements apply for building construction that being a S-2?

 

[RLGA]

if it is a type IIb construction, non-separated mixed use B, R-2 and S-2, would the most restrictive requirements apply for building construction that being a S-2?

You still have to provide the required dwelling unit separation from "other occupancies contiguous to them in the same building" per IBC Section 420.2. The required separation is only a fire partition, not a fire barrier as required for occupancy separation.

 

[Tim Mailloux]

You still have to provide the required dwelling unit separation from "other occupancies contiguous to them in the same building" per IBC Section 420.2. The required separation is only a fire partition, not a fire barrier as required for occupancy separation.

what he said.

 

[steveray]

I am sure I could work with whatever is less restrictive.....But DU sounds right....Separation Might get messy if it sprawls a bit, but we are only talking about a 30 min rating right...

 

[Tim Mailloux]

I am sure I could work with whatever is less restrictive.....But DU sounds right....Separation Might get messy if it sprawls a bit, but we are only talking about a 30 min rating right...

The 30 minute rated partitions are no big deal, its then having to buy rated doors, rated door hardware, fire dampers at all the duct penetrations, and fire safing all thru wall penetrations. That stuff really adds up.

 

[steveray]

Damper exception....

717.5.4 Fire partitions. Ducts and air transfer openings
that penetrate fire partitions shall be protected with listed
fire dampers installed in accordance with their listing.
Exceptions: In occupancies other than Group H, fire
dampers are not required where any of the following
apply:
1. Corridor walls in buildings equipped throughout
with an automatic sprinkler system in.......
4. Such walls are penetrated by ducted HVAC
systems, have a required fire-resistance rating
of 1 hour or less, and are in buildings equipped
throughout with an automatic sprinkler system
in accordance with Section 903.3.1.1 or
903.3.1.2. For the purposes of this exception, a
ducted HVAC system shall be a duct system
for conveying supply, return or exhaust air as
part of the structure’s HVAC system. Such a
duct system shall be constructed of sheet steel
not less than No. 26 gage thickness and shall be
continuous from the air-handling appliance or
equipment to the air outlet and inlet terminals.

And oddly enough, call it a fire barrier and it gets easier because too many stupid people are involved in code development and I don't have enough time to fix it all:

717.5.2
3. Such walls are penetrated by fully ducted HVAC
systems, have a required fire-resistance rating of
1 hour or less, are in areas of other than Group H
and are in buildings equipped throughout with an
automatic sprinkler system in accordance with
Section 903.3.1.1 or 903.3.1.2. For the purposes
of this exception, a fully ducted HVAC system
shall be a duct system for conveying supply,
return or exhaust air as part of the structure’s
HVAC system. Such a duct system shall be
constructed of sheet steel not less than No. 26
gage thickness and shall be continuous from the
air-handling appliance or equipment to the air
outlet and inlet terminals. Nonmetal flexible air
connectors shall be permitted in the following
locations:
3.1. At the duct connection to the air handling
unit or equipment located within the
mechanical room in accordance with
Section 603.9 of the International
Mechanical Code.
3.2. From an overhead metal duct to a ceiling
diffuser within the same room in accordance
with Section 603.6.2 of the
International Mechanical Code.