Run cat5 to smoke detectors for alarm?


Active Member
Unfortunatley I do not know the brand or model of the smoke detectors being installed in my home but I do know that they are all run off 110v and that they will not be linked to my alarm system.

Can I just run a cat5 cable to the smoke detector closest to the alarm system and then later upgrade that detector? I read that when one alarm goes off on the 110v models, they all go off, if this is the case then I am making a big assumption that I can upgrade any one of the smoke detectors and wire it into the alarm system.
Those smokes usually cannot be tied into an HA system unless they have a contact relay on them. I would leave those in place and just wire for additional smokes tied into your system. But technically you should use 'firewire' which I believe is 18 gauge and is in a red fire rated jacket. It is expensive cable, but the right way to do it. At the least I would use the same 22ga wire for your sensors and not Cat5 unless you're planning on doubling up the conductors.
Does anyone have a source for a small quantity of this cable? I keep seeing 500' and 1000' rolls... I dont need much 50' MAX.

I did see a few on ebay but it is either 12 14 or 22 awg. I also thought about buying a spool and reselling the rest... but would prefer a small amount if I could find it.
mustangcoupe said:
Does anyone have a source for a small quantity of this cable?
HERE they have 300 ft of Cat5e, plus RJ-45 connector ends, PLUS a crimper for $32 shipped. The only thing is it is "general purpose rated/ UL approved" so there are limitations on where you can run it in your walls/attics.

Sorry for the confusion... I am looking for 18/2 or 18/4 fire rated wire for smoke detector install. Got plenty of cat5 :)