Guide For The Installation Of Smoke Detectors In One And Two Family Dwellings
The placement and operation of smoke detectors in new and certain remodeled one and two family dwellings is regulated under the State Building Code 780 CMR
A permit from the Fire Department is required to install or make alterations to any fire alarm and detection system. Plans for the proposed alarm and detection system shall be submitted to the Fire Department for review and approval. Plans should include a description of the planned alarm system and proposed detector locations. Floor plans should be submitted and shall include the location of all required fire protection systems and heating systems storage areas (780 CMR 5110.7).
Smoke detectors must be installed 1. In all new construction of one and two family dwellings. 2. When one or more sleeping rooms are added or created, smoke detectors must be installed in the entire building to the requirements for a new building. 3. When the extent of renovation work creates the opportunity to install smoke detectors (the Building Commissioner and Fire Department will make the determination).
System requirements 1. The smoke detectors or alarm systems must have primary (AC) power and monitored battery back up power (780 CMR 5313.2.5.2 and 5313.2.5.3). 2. Smoke detectors shall be of the photoelectric type (780 CMR 5313.1). 3. When a combination smoke detector and Carbon Monoxide (CO) detector is used, the simulated voice and tone alarms shall clearly distinguish between CO and fire notification in accordance with NFPA 720: 5.3.4 (780 CMR 5313.1). 4. The alarm sounding devices must be rated at 85 dB (at 10 feet) and must provide a sound level of not less than 75 dB in the bedrooms with the doors closed (780 CMR 5313.2.4). 5. When more than 12 smoke alarms are installed, monitored system-type devices must be utilized (780 CMR 5313.2.1). This system-type household fire warning system must be wired as below in #6 (780 CMR 5313.2.5.2). Primary electrical power for single and multi-station devices shall be supplied from a permanently wired connection directly to an AC primary power source. This can be either: a dedicated locked branch circuit or a single branch circuit which also provides other electrical service to a habitable space (780 CMR 5313.2.5.1).
Page 1 of 4 Amherst Fire Department Guide to Smoke Detectors in 1 and 2 Family Dwelling
6. All household fire-warning systems shall also have secondary (standby) power supplied from monitored batteries in accordance with NFPA 72. For fire alarm control units (panels) and wireless systems, the panel battery shall serve as the source of secondary electrical power (780 CMR 5313.2.5.3). 7. The sounding of any detector (required and non-required) shall cause all detectors to sound throughout the building. In a two family dwelling the smoke detectors in each unit are interconnected. The smoke detectors shall not be interconnected between units. All common area smoke detectors shall be interconnected and shall be clearly audible in all bedrooms.
Smoke Detectors must be installed 1. Inside all bedrooms. 2. Outside each separate bedroom in the immediate vicinity of the bedroom. 3. On each level of the dwelling, including basements, but not in attics and crawl spaces . 4. Near the base of the stairs when such stairs lead to another occupied space. 5. One smoke detector shall be provided for each 1200 square feet. 6. In two family dwellings, smoke detectors shall also be located: In all common hallways In all common basements In all common stairways on each level outside the dwelling unit doorway 7. Photoelectric smoke detectors are permitted to be placed closer than 3’ horizontally from a kitchen or bathroom when hallway or other room size restricts detector mounting options. 8. Smoke detectors shall be mounted on the ceiling at least 4 inches from a wall or on a wall with the top of the alarm not less than 4 inches nor more than 12 inches below the ceiling. 9. Heat detectors are not required except as listed below. If used, heat detectors must be listed for use with the installed smoke detectors. (780 CMR 5313.2.9, 5313.2.10, 5313.2.11, and 5313.2.12)
Heat Detectors must be installed 1. In any integral garage or attached garage. 2. In any new addition attached garage to an existing dwelling – requires a single heat detector installed in the garage. 3. The required heat detector shall be interconnected with the house detection system when the systems are compatible. If the systems are not compatible the heat detector shall be connected to an audible notification appliance located in the dwelling and within 20 feet of the nearest door to the garage from the dwelling. No additional audible alarm notification device is required in the garage. 4. Heat detectors shall be placed on or near the center of the garage when the ceiling is a flat-finish ceiling. When the ceiling is sloped, the heat detector shall be placed in the approximate center of the vaulted ceiling, but not closer than 4 feet to any wall. (780 CMR 5313.3.1, 5313.3.2, and 5313.3.3)
Page 2 of 4 Amherst Fire Department Guide to Smoke Detectors in 1 and 2 Family Dwelling
Carbon Monoxide Detectors must be installed: 1. In accordance with 527CMR 31.00 and 248 CMR. 2. CO detectors shall have secondary power supplied from monitored batteries in accordance with NFPA 72 (as with smoke detectors) and be either: Listed, interconnected 120 volt, or Listed, low-voltage combination system, or Listed, wireless system. 3. Required CO detectors are not required to be interconnected to the required household fire warning system, but where interconnection is desired, such CO detectors shall be compatible with the fire protection devices. 4. CO detectors must be installed: On each story of a dwelling unit, including basements and cellars (but not including crawl spaces and uninhabitable spaces) When mounting a CO detector on a story with a bedroom, the detector shall be located outside a bedroom, no more than 10 feet outside of any bedroom door. 5. All CO detectors shall have a minimum rating of 85dBA at 10 feet. 6. CO detectors shall be installed in accordance with the manufacturer’s instructions and the applicable requirements of NFPA 720. (780 CMR 5313.4, 5313.4.1, 5313.4.2, and 5313.4.3)
Fire Sprinkler Systems An NFPA 13D system is required in new construction in one and two family dwellings having an aggregate area greater than 14,400 square feet. This area includes the basement, but does not include the garage or unfinished attics (780 CMR 5313.5.1).
Requirements for Construction Documents These requirements apply to 1 and 2 family dwellings, not more than 3 stories in height. The addition or alteration of Fire Alarm Systems requires a Permit from the Fire Department. The form “APPLICATION FOR PERMIT, To Install a Fire Alarm System in 1 and 2 Family Dwellings, M.G.L. Chapter 148,” shall be completed and submitted to the Fire Department with the following documents: Floor Plans including Basement and Attic levels. Floor Plans shall include type and location of all required fire protection devices and heating systems storage areas. Locations of ceiling fans and ceiling/wall heating vents should be noted so as to appropriately place smoke detectors. (780 CMR 5313.7)
Page 3 of 4 Amherst Fire Department Guide to Smoke Detectors in 1 and 2 Family Dwelling
Testing and Acceptance: TWO Inspections Are Required: A Rough Inspection and a Final Inspection/ Alarm System Test.
1. Call the Fire Department at 259-3080 to schedule the Rough Inspection and the Final Inspection/ Alarm System Test. 2. The Fire Department shall be contacted after all devices have been located and wired but before sheetrock has been installed for a Rough Inspection. 3. After all work is complete, test all smoke detectors, warning devices and supervisory systems (if installed), then call the Fire Department to schedule the Final Inspection/ Alarm Test. 4. At the time of both the Rough Inspection and the Final Inspection/ Alarm Test, the transmittal sheet and the plans showing the approved smoke detector placement shall be on site. 5. The installer or person familiar with the operation of the system must be on site to discuss and operate the system during both tests.
The installation of detection equipment and alarm systems must conform to the requirement of the Massachusetts Building Code (780 CMR), NFPA 72 National Fire Alarm Code and the Fire Prevention Code ( MGL Chapter 148 and 527 CMR).
If you have any questions or would like assistance reviewing the requirements for your project, call the Fire Department at 259-3082.
Page 4 of 4