I need to place a smoke alarm on my first floor (no sleeping areas). There is a wall portal with a 15" lintel (see image) between the living room and the dining room.
I am unsure whether one alarm is adequate for both of these areas. My understanding is that smoke in either of these areas would tend to hug the ceiling and therefore, I would think that there would have to be a lot of smoke before it would begin to dip below the lintel into the other area. Assuming only one alarm in either area, my concern is that this could significantly delay the alarm. So, I wonder if the right solution is to install an alarm in each of these areas.
In the event of a fire, would enough smoke be in the air to trigger an alarm in either area or would the lintel tend to localize the smoke to one area and thus delay the alarm?
Best Answer
Yes and fantastic question, the lintel/header/apron will absolutely delay detection...by quite a lot. Therefore, I absolutely agree with Jack that you need to place the detector closer (the lintel side that's closer to the threat) to the known threat area or even just within the shortest path from that area. Which, may not involve this lintel nor these rooms.
An abundance of appliances is always your biggest culprit indicator, not that a TV or outlet's wiring could be faulty... though they would've typically revealed themselves with early symptoms.
I would suggest either a ceiling placement of the detector or a high wall placement that results in the detector being very close to the crown molding. The ceiling will fill with smoke long before it escapes beneath the lintel/header/apron.