Question:
I recently had a house fire which severely damaged my home. The fire alarm system I had installed (heat detectors in attic, kitchen and garage; smoke detectors in hallways) worked...to an extent. The fire was caused by a plumber soldering a fitting in the main water supply to the house. He was doing this in a small hole cut in the siding. He apparently ignited the paper between the siding and a stud adjacent to the pipe. On the other side of the stud was a 5" channel between the next stud that _had no insulation whatsoever_. The fire migrated across the stud into the channel, which basically acted as a chimney, taking the fire up into the attic. Within minutes, fire was sweeping through the attic. Fortunately, we were home at the time. The plumber banged on the door and told us to call the fire department (then he ran off, the useless jerk). My wife dialed 911 and reported the fire. I was in the house when the alarm sounded. There was no smoke inside (single-floor dwelling) at the time, so I have to assume that the alarm was tripped by the attic heat detector melting down. My wife was still on the phone with the fire department when the alarm sounded (she was on a cordless phone in the front yard). The system grabbed the phone line, as it should have, and presumably it atttempted to dial the monitoring service. However, the alarm company later reported that they never received the call. The assumption is that at this point all the small wires in the attic (phone, intercom, alarm, etc.) were melting down. (The heat detector was located in the center of the house, about 40 feet from the source of the fire -- I believe this was a 175-degree detector). In the space of just a few minutes the alarm siren and strobe light ceased operation. The fire investigator sent by my insurance company told me that has seen many instances like this where the dialup alarm did not succeed because of fire or heat damage to the phone or alarm system. We put the heat detector in the attic in the hope that in case of a lightning strike or problem with furnace or water heater (usually located in the attic in southeast Texas) the monitoring company would be notified of a problem if we were not at home. In view of what happened to the house, this scenario is flawed. Had we not been at home, the house would have been lost (as it was, there was significant damage to a portion of the house, but no loss of personal effects or pets). I wonder if the chicken plumber would have bothered to call anyone if he knew nobody was home. So, now that we will be rebuilding, we are interested in ideas on ways to strengthen the possibility of getting through to the monitoring company in the event of a thermal event in the attic, and perhaps in extending the operation of the alarm system in such an event. My wife has suggested running the phone line (at least the one to the alarm panel) through a conduit, and perhaps using plenum-rated line at that. The fire investigator thought this was a pretty good idea. I'm also aware of wireless devices that are available. The fire investigator feels these are OK, but is just wary of possible additional problems that could be caused by more complex devices. I'd be interested in any thoughts, ideas or experiences y'all might have so that we can rethink our fire detection strategy for the "new" house. I am already planning to use the fax/data line for the alarm instead of the voice line so that a 911 call in progress is not interrupted.

Answer: Q: My wife was still on the phone with the fire department when the alarm sounded (she was on a cordless phone in the front yard). The system grabbed the phone line, as it should have, and presumably it atttempted to dial the monitoring service. However, the alarm company later reported that they never received the call. The assumption is

A: Have you tested that this is even possible? The alarm would need to grab the line by: disconnecting everything, WAITING, connecting, listening for dial tone, etc. Many times it seems the WAITING step is left out or is too short for the phone company to actually turn around and give you another tone. I have even seen situations where the equipment used a single double-throw relay just like a modem (the phone line is either connected to everything else or connected to the dialer). That just won't work reliably in the best of conditions.