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Smoke detector in skylight shaft

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alexTheBuilder

Civil/Environmental
Sep 4, 2009
3
Hi,

I have a living room that is 16' x 18' in size. There is a skylight shaft in the middle that has 2 2'x4' skylights with 4/12 pitch and a shaft that flares out 1' to all sides, so the ceiling opening to the shaft is roughly 6'x6'. The highest point of the skylights is about 4' higher than the ceiling. Location of the building is San Jose, CA.

The living room has a door to a bedroom, so it needs a smoke detector. Do I need to place the smoke detector in the skylight shaft, because it's the highest point of the room? The rule to place a smoke detector 3' away from the highest point is hard to realize, because it would place it either in a skylight window or outside of the shaft.

I it customary to put residential smoke detectors in skylight shafts? If you know of any codes that require or forbid this, could you point me to this?

Thanks,
Alex
 
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with out a floor plan a little hard to give an answer

I would not but them in the skylight

I think you are good to go if you put them on the ceiling



Is the ceiling flat except for the skylights, as in not vaulted???
 
A smoke detector is not a smoke alarm. Install the smoke alarm in accordance with NFPA 72 and its instructions.
 
Hi,

thank you for your responses so far. I have added a plan of the living room in question. The background is that a city building inspector has mandated us this unusual location of a smoke alarm, but we are unsure whether...

1. this location is really required acording the NFPA 72 or another location outside the skylight shaft would do.
2. it is optimal for fire safety.
3. regular residential smoke alarms will perform optimally given the installation angle and location.

Thank you for your help!

Regards,
Alex

3894984239_d2ddffb578_b.jpg
 
I forgot to mention: The skylights can be opened, they hinge open to the lower portion of the skylight. Could an open skylight influence the functionality of the smoke alarm by diverting the smoke away from the smoke alarm location? Is there a passage in the NFPA 72 about this?
 
I think I would stick it before the bedroom on the 8 foot soffit area
not sure what building code you are under

but most require it before the bedroom, and do not require the entire room in which the access to the bedroom to be protected. you might throw one in some where at the nie foot level just to make the inspector happy, do not think that one is needed in the skylight, and also look at the listing of the detector as far as low and hig temp it can be exposed to
 
another thought is that you are trying to protect the bedroom, no the room prior to the bedroom,

so most of the time would wnat to see the smoke alarm very near the bedroom,

but not more than fifteen feet away from the bedroom door.
 
sorry I say smoke detector you say smoke alarm

depends on the setting

and which way the wind is blowing
 
11.1.3 The requirements of Chapter 4 through Chapter 9 shall not apply unless otherwise indicated.


11.5.1* Required Detection
11.5.1.1* Where required by applicable laws, codes, or standards for a specific type of occupancy, approved single- and multiple-station smoke alarms shall be installed as follows:
(1)* In all sleeping rooms and guest rooms
(2)* Outside of each separate dwelling unit sleeping area, within 6.4 m (21 ft) of any door to a sleeping room, the distance measured along a path of travel
(3) On every level of a dwelling unit, including basements
(4) On every level of a residential board and care occupancy (small facility), including basements and excluding crawl spaces and unfinished attics
(5)* In the living area(s) of a guest suite
(6) In the living area(s) of a residential board and care occupancy (small facility)



11.7.2* Smoke Alarms and System Smoke Detectors. Each device shall detect abnormal quantities of smoke, shall operate in the normal environmental conditions, and shall be in compliance with applicable standards such as ANSI/UL 268, Standard for Safety Smoke Detectors for Fire Alarm Signaling Systems, or ANSI/UL 217, Standard for Safety Single and Multiple Station Smoke Alarms.



11.8 Installation.
11.8.1 General.
11.8.1.1 All equipment shall be installed in accordance with the manufacturer’s published instructions and applicable electrical standards.



11.8.3* Smoke Detectors and Smoke Alarms. Smoke alarms, smoke detectors, devices, combination of devices, and equipment shall be installed in accordance with the manufacturer’s listing and published instructions, and unless specifically listed for the application, shall comply with requirements in 11.8.3.1 through 11.8.3.5.




11.8.3.1 Flat Ceilings. Smoke alarms or smoke detectors mounted on a flat ceiling shall be located no closer than 102 mm (4 in.) from the adjoining wall surface.
11.8.3.2* Peaked Ceilings. Smoke alarms or smoke detectors mounted on a peaked ceiling shall be located within 914 mm (36 in.) horizontally of the peak, but not closer than 102 mm (4 in.) vertically to the peak.
11.8.3.3* Sloped Ceilings. Smoke alarms or smoke detectors mounted on a sloped ceiling having a rise greater than 1 m in 8 m (1 ft in 8 ft) horizontally shall be located within 914 mm (36 in.) of the high side of the ceiling, but not closer than 102 mm (4 in.) from the adjoining wall surface.
11.8.3.4* Wall Mounting. Smoke alarms or smoke detectors mounted on walls shall be located not closer than 102 mm (4 in.) from the adjoining ceiling surface and not farther than 305 mm (12 in.) from the adjoining ceiling surface.





11.8.3.5 Specific Location Requirements. The installation of smoke alarms and smoke detectors shall comply with the following requirements:
(1) Smoke alarms and smoke detectors shall not be located where ambient conditions, including humidity and temperature, are outside the limits specified by the manufacturer's published instructions.
(2) Smoke alarms and smoke detectors shall not be located within unfinished attics or garages or in other spaces where temperatures can fall below 4°C (40°F) or exceed 38°C (100°F).
(3) Where the mounting surface could become considerably warmer or cooler than the room, such as a poorly insulated ceiling below an unfinished attic or an exterior wall, smoke alarms and smoke detectors shall be mounted on an inside wall.
(4) Smoke alarms and smoke detectors installed within a 6.1 m (20 ft) horizontal path of a cooking appliance shall be equipped with an alarm-silencing means or be of the photoelectric type.
(5) Smoke alarms and smoke detectors shall not be installed within a 914 mm (36 in.) horizontal path from a door to a bathroom containing a shower or tub.
(6) Smoke alarms and smoke detectors shall not be installed within a 914 mm (36 in.) horizontal path from the supply registers of a forced air heating or cooling system and shall be installed outside of the direct airflow from those registers.
(7) Smoke alarms and smoke detectors shall not be installed within a 914 mm (36 in.) horizontal path from the tip of the blade of a ceiling-suspended (paddle) fan.
(8) Where stairs lead to other occupied levels, a smoke alarm or smoke detector shall be located so that smoke rising in the stairway cannot be prevented from reaching the smoke alarm or smoke detector by an intervening door or obstruction.
(9) For stairways leading up from a basement, smoke alarms or smoke detectors shall be located on the basement ceiling near the entry to the stairs.
(10)* For tray-shaped ceilings (coffered ceiling) smoke alarms and smoke detectors shall be installed on the highest portion of the ceiling or on the sloped portion of the ceiling within 305 mm (12 in.) vertically down from the highest point.
 
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