Where to install a smoke detector and its location are just as important as having this lifesaving device installed. Placing a smoke detector in the wrong location could delay your response to smoke or even prevent an alarm from going off.
Although you should install smoke detectors following device manufacturers’ guidelines and NFPA (National Fire Protection Association) standards, your local jurisdiction might have a different idea. This idea is usually LESS smoke detectors: Chicago is one of the examples.
Since we are talking about your life, following only a minimum requirement is not enough; For literally a few dollars more, you can get maximum protection.
Proper placement of a smoke alarm per IRC (International Residential Code), IBC (International Building Code), and NFPA:
New building:
- Smoke detectors must be hardwired (powered from electrical panel) and require battery backup. Your jurisdiction may require a dedicated circuit for this purpose; if not required, make sure your smoke detector has not been installed on a circuit / connected to wall switch controlled ceiling light or outlet receptacle. Putting a smoke alarm on a GFCI protected electrical circuit is also not a good idea.
- Do not use rechargeable type batteries for smoke detectors, a good quality alkaline type battery is the right choice. Smoke alarms will emit a signal when the batteries are low; Please replace the battery with a new one as soon as you hear that repeating sound.
- Smoke detectors are required in each bedroom and adjoining bedroom. As I mentioned earlier, some jurisdictions require less: Chicago is one example where smoke detectors are not required inside the bedroom/sleeping area. Instead, you must install a smoke alarm within 15′ of the bedroom entrance. In larger houses/apartments, where rooms are located more than 30 feet apart, two or more smoke detectors may need to be installed.
- At least one is required on each floor of the house and in the basement. Crawl spaces and uninhabitable attics do not require the installation of a smoke detector. However, if your attic or basement contains a furnace, water heater, or any appliance that could become a source of fire (gas, oil, electricity), also install a smoke alarm (required in some jurisdictions and highly recommended if not). required).
- Smoke detectors must be interconnected: one triggered smoke detector activates all of them. Not all types of smoke detectors have the “interconnect” feature, which is extremely important: smoke developing in one section of the house would automatically activate the nearest device all at the same time.
existing building:
During remodeling, it is not necessary to update electrical wiring to interconnect existing smoke alarms unless wall finishes are removed and wall framing is exposed. However, even without rewiring, you can still achieve maximum protection by using an interconnected wireless smoke detection system.
- The smoke alarm must be clearly audible in all bedrooms above background noise levels with all intervening doors closed. This is why periodic testing of your smoke detector siren is so important, just like any mechanical/electronic device, it sometimes fails.
- Enclosed interior stairwells also require a smoke detector, and one must be installed on the top floor ceiling. The stairs act as chimneys and the smoke coming up from the lower floor would activate the device and give you advance notice.
Smoke Detector Location: Rules apply to all locations described above.
This is extremely important and at the same time quite simple, unfortunately very often it is done completely wrong. It’s probably because we don’t like to read manuals and often assume we know what we’re doing.
- When installing a smoke alarm on the ceiling (preferred location/may be required in some jurisdictions), place it as close to the center as possible, never closer than 4″ (10 cm) from the side wall or corner.
- If for some reason, ceiling mounting is not practical and wall mounting is permitted, smoke detectors may be mounted on the wall with their top edge a minimum of 4″ (10 cm) and a maximum of 12″ (30.5 cm) below the ceiling. .
Before placing a smoke detector on the ceiling or wall, consider checking the insulation of the house. Older homes may be missing a roof (if it’s open to the attic) or insulation on exterior walls. This would allow the transfer of extreme heat or cold from the outside into the house, creating a thermal barrier and preventing smoke from reaching/triggering the alarm. If this is the case (it can simply touch the wall or ceiling on very hot or cold days), mount a smoke detector on an inside wall of the house.
- Install smoke detectors in rooms with cathedral, sloped, peaked, gabled ceilings 3′ or less from the highest point (measured horizontally).
- Install smoke detectors in each section of the room/area that has been divided by a partial wall. The wall could be descending from the ceiling (at least 24″) or from the floor.
- Install smoke detectors in a tray ceiling (also called a coffered ceiling) at the highest part of the ceiling or on the sloped part of the ceiling within 12″ (30.5 cm) vertically down from the highest point.
DO NOT install smoke detectors in the following areas to minimize the possibility of false alarms:
- Areas where combustion particles are present (combustion particles: the by-products of the combustion process)
- garages
- stuffy kitchens
- near furnaces and water heaters: I would disagree with this one, because the presence of those particles would be a sign of problems in the combustion process
If you choose to install one in those areas, the photoelectric-type smoke alarm might be less annoying.
- Humid or very humid areas such as bathrooms. Humidity levels after taking a hot shower can trigger a false alarm.
- Within 3′ of forced air heating and/or cooling system air supply vents, in direct airflow area, near whole house fan locations. High airflow could blow smoke or blow it away from the detector preventing it from responding correctly or at all.
- Near fluorescent lights, where electronic “noise” may cause nuisance alarms.
- Dusty areas, where dust particles could cause smoke alarm failure or false alarm
- In areas where air temperatures can drop below 40°F (4°C) or rise above 100°F (38°C)
- Avoid areas near doors and windows while installing a smoke alarm
If you’ve made it this far, I hope you have more than a general idea of where to install smoke detectors in your home and what the optimal smoke alarm placement is.