Wire for smoke alarms?

[nmbexcuse]

I am in the middle of the whole house remodeling and my electrician who is doing wiring for me told me I should have him wire for smoke alarms for all the rooms while he is at it.

Is this worth the effort? I was planning on just using battery operated ones that you attach to the ceiling with a double sided tapes and only in the kitchen, garage and the family room where a fire place is located.

What is the benefit of having a smoke alarm that is hard wired? I asked him and he said that if it's hard wired and chained together, then if one goes off all goes off, ok so this is a slight plus.

Comments?

MC

[Zephyr]

Thats the code now adays, - if you are pulling wire thru the area anyways, why not, the extra cost is definitly worth a life.

Dave

[Red Green]

[e-mail] wrote in news:78afbbab-b2ca-4dfb-aabd- [e-mail]:

Well, no battery changing.

No annoying chirping when batteries get weak.

Code often requires at least one wired one on each floor.

If there is a fire it sure would be nice if they all went off so everyone has the earliest possible warning.

As long as if one becomes defective the whole damn lot doesn't start chrping!

[RickH]

Thats code, your electrician is right its not a bad idea to do it now. You will still have the chirping when batteries go low. The idea is that the batteries parallel the house power, the house power does not replace the need for batteries and they will still chirp and are monitored for weakness. But the alarms will be synched up and continue to work even on a dead battery until you get the battery replaced.

[Mark]

Careful with this advice - I think even the hardwired detectors often have a battery backup in case of a power failure. Check out sites like:

to see some options.

[N8N]

yeah, what they all said. should just be 14/3 to an octagon box in each room, well worth it if the price is reasonable.

nate

[RBM]

You need to find out the code in your area. Many jurisdictions require 120 volt with battery backup, interconnected, one unit on each level, and one unit in each bedroom. Two locations where you don't install smokes is in the garage or kitchen

[Red Green]

"Mark" wrote in news:47b2120a$0$22814$ [e-mail]:

Thanks. I stand corrected.

[RBM]

yeah, what they all said. should just be 14/3 to an octagon box in each room, well worth it if the price is reasonable.

nate Hey Nate, let the electrician pick the box!!!

[J.A. Michel]

This is a good idea and well worth the effort. When they are all wired, if one goes off, they all go off.

[gfretwell]

The code also requires battery backup so you still get the chirp.

The electrician should be pulling 14/3 romex

[John McGaw]

All of mine do have backup batteries but they are providing no operating current so the batteries last roughly as long as their shelf life. And with good alkalines this is a _very_ long time.

[nmbexcuse]

I am doing everything in EMT. So far over 200' of new EMT has been laid on top of the existing EMT pipes. I don't know if I can fit extra wires into what I have already. If it involves new rigid conduits to be laid the cost will not be insignificant. I hate to use romex.

[nmbexcuse]

Why not the kitchen?

I would think the kitchen is the most likely smoke induced location. If you leave a stove on and went to talk on a phone and then things get burnt etc...

[G. Morgan]

[e-mail] wrote in news:78afbbab-b2ca-4dfb-aabd- [e-mail]:

Yes, have him wire 110V in all the bedrooms and outside the common sleeping areas at the minimum. Also wire a 18/4 FPL to each detector in a "daisy chain" fashion + one back to the alarm panel if you have one.

[Nate Nagel]

That's a good point, if you ever think you want to add a fire alarm panel or security system that monitors your smoke detectors as well, you should pull some extra wire. should NOT be in the same conduit as

120VAC as 24VEDEC is typical; you could free-run plenum rated cable however (FPLP) you'll need two conductors to all smokes and don't t-tap. If you do this the smokes you use should have auxiliary alarm relay contacts. The reason for not t-tapping is for supervision of the wiring; there will be an end of line resistor (or other device, but I can only think of one panel off the top of my head where it's not a resistor and it's not one likely to be installed in a residence) at the last detector so the panel can check and see if it sees that resistor to monitor the loop for integrity.

nate

[RBM]

That's it exactly, you don't install them in rooms where smoke occurs in normal use. If necessary, you'd use rate of rise heat detectors, besides you don't need your entire house screaming at you to tell you that you burned the toast

[G. Morgan]

Yeah, FPLP would be best (Fire Power Limited Plenum rated). I suggested 18 gauge 4 conductor cable to cover 4 and 2-wire smokes (in case the alarm panel is not compatible with 2-wire smokes). It's better to use 2-wire smokes because they require less current generally and do not require a EOL supervision relay module (still need to place a EOL resistor at the last detector).

If no alarm panel is in use for now, the wire can be used for the interconnect (which is required) so all sounders go off if one detector trips. And at least you'll have the capability to add a monitored fire alarm in the future.

You might also want to pre-wire for heat detectors in the garage, kitchen, attic, furnace closet, hot water heater closet...

Pre-wire for CO detectors on each floor.

[Nate Nagel]

I can't imagine wanting to use 4-wire detectors in a residential environment; typically it would just be 120VAC single station tandem units with aux. relays for optional monitoring.

I suppose, if one had access to a warehouse of old fire alarm parts (well, um, I do...) one could install an old FA system in one's house like a Simplex 2001 or Pyro System 3 but I'm not sure why you'd want to :)

nate

"May I have your attention please. May I have your attention please. Hazardous gas has been detected in the second floor restroom. Hazardous gas has been detected in the second floor restroom. Please leave the building by the nearest exit. Do not use the elevators."

[whitejag]

We use both types (code) right next to each otherr - not the backup- electrical type, they get zapped sometimes - most residential fires knock the power out soon after starting, real soon. If not started by the electrical in the fist place... change the batteries twice a year: dayight savings time / standard time.