Arc Fault Circuit Interrupter placement....

[MikeT]

I know the current electrical code requires that receptacles in bedrooms be protected with an AFCI breaker.  In my house that I am building, I have my lights for my bedrooms on one circuit and my outlets/receptacles on another.  So I assume I can go with only one AFCI breaker  for the receptacles.

My questions concerns the wisdom in investing in AFCI breakers for the other rooms where I will have receptacles.  The way I wired my house, I have lights on separate circuits from outlets. 

The AFCI breakers are way more expensive (ca. $33 compared to $3 for a regular 15 A breaker), so I do not want to throw money away, but then again, it seems like a small amount if we are talking about safety.

Thoughts?....

[MountainDon]

What you need and in which circuits depends on which NEC code your area uses. The 2008 NEC has extended the requirements to virtually every room people may occupy. • Bedroom • Living room • Dining room • Sun room
• Hallway • Closet • Finished basement • Rec room. Doesn't leave much.

There is also a new type of AFCI, the Combination AFCI. The way I understand it the previous ones could detect faults between two different wires. That would usually be in a cord plugged into the outlet. The combination unit also can detect loose connections within one wire, such as arcing in a loose connection, be it at the house wire that connects to the outlet, or a poorly fitting plug in contact.

A hard wired smoke detector in a bedroom has to be on an AFCI line. A switched outlet, including the switch, must be on an AFCI.

[MikeT]

I will have to check with my inspector, I guess.  Out here in Oregon, the AFCI aren't so prevalent that their price has dropped much at all.  In the scheme of things, it isn't that big a deal.  But when you have six breakers in your hand and the price for the regular ones is 18 bucks and then you realize the ones you are now required to utilize cost $180, it can be a bit disheartening....

[MikeT]

So I emailed the electrical inspector for the county.  Here are my questions and his responses:

I have my circuits split between lighting circuits and circuits with receptacles.  Here are my questions:

-I know I have to have AFCI protection on the receptacle circuit for the bedrooms, but do I need to have AFCI protection on the receptacle circuits elsewhere?                 no

-Do I need AFCI protection for the lighting circuits in the bedrooms?        Yes

-Does my circuit for my smoke detectors need to be protected with an AFCI breaker as well?    no

Thank you for any help you can lend me.

Best,
Mike

The plugs and lights in the bedrooms are the only outlets (lighting outlets and receptical outlets) required to be afci protected.

[MountainDon]

The plugs and lights in the bedrooms are the only outlets (lighting outlets and receptical outlets) required to be afci protected.

In Mike's situation.  Others may find they are working under different rules. Electrical is subject to different rules in different places; one o those things one should check locally. But the question does make or interesting conversations. Plus it is interesting to see the differences across the country.

[JRR]

I wonder if there is any chance to avoid the need for AFCI protection on wall switches for lighting .... by using low voltage on the switches that, in turn, energizes isolation relays to switch the higher voltages to the lamps?

[MountainDon]

 

The present code makes no specific mention for low voltage circuit exemption, so my bet is that you would have trouble talking that one through.

Seems to me it is a complication that might cost more than the price of an AFCI   as well as complicate the wiring. More wiring would be needed, plus a place for the relays, the relays themselves... 

[MikeT]

I haven't done any research on this, but my guess is that the wave of the future will be that many more circuits will be required to have AFCI protection.  When they get more use, the prices will (hopefully) drop.  For us DIYers, it seems like a big increase in price.  But when you are hiring an electrician to do a job, the increase in these prices will not seem so large because it get swallowed in the overall price. 

[MountainDon]

Right Mike. Eventually the cost should down, maybe not to the level o an ordinary breaker today. And it is a pretty sure thing that virtually all the circuits in a home will be required to have AFCI, as the 2008 NEC indicates. And if you have to go that far, why exempt any circuits at all? 

This is not bad as far as costs go. The one I don't like is the new rule on residential fire suppression systems. Right now our city has already that anyone wanting to receive a home child care license for 6 to 12 children (2 adult care givers) must retro fit such a system to their home. They are using that rule as a back door way to make home child care prohibitively expensive to get into. But that's another rant.

As far as the risk of dieing in a residential fire there are many more human activities that are much more likely to cause your death. I say put the money where it will benefit the most. Residential sprinkler systems are guaranteed to enrich the the fire protection industry. Hmmmm, that could also be said about the AFCI's.    Electrical faults actually don't cause all that many residential fires. Research just showed me that cooking accounts for the most fires (26%).

http://www.usfa.dhs.gov/statistics/national/residential/loss_fire.shtm

[MikeT]

Regarding the fire sprinkler system question (which we have discussed here a lot, I realize): I am resistant to hiring someone to do it, but I keep looking for the DIY system that will allow me to run it off my fresh water.  I know it is possible, but I have not found the right set of instructions.  If I get the system in, I know my insurance will drop, so I look at it as a front end hassle with payback in the short to medium term. 

For the AFCIs, I was halfway thinking about just doing each receptacle circuit, but I might as well go with the minimum required right now, since switching later is quite easy. 

The same cannot be said for the sprinkler--a retrofit is more hassle and costly that here in the final parts of my rough stage.

Best,
mt

[JRR]

..... Research just showed me that cooking accounts for the most fires (26%).
.....

Ah!  So now I understand why she refuses to cook, and suggests we sell the kitchen!

[davidj]

Electrical faults actually don't cause all that many residential fires. Research just showed me that cooking accounts for the most fires (26%).

http://www.usfa.dhs.gov/statistics/national/residential/loss_fire.shtm

The data is really interesting - cooking accounts for most of the fires but few of the deaths.  "Incendiary, suspicious" accounts for most of the death and damage, with cooking fires not killing too many folks.

It looks like something around $80 million/year of damage is due to electrical distribution failures, and maybe 100 deaths (roughly 3% of 3000 deaths in residential fires).  Something like 1 million new homes sell each year in the US.  If you spend an extra $200/house on breakers, and (guessing) it saves half of the electrical distribution fire deaths and damage at some point down the line, then you're saving 50 lives and $40million of damage at a cost of $200 million each year.  This comes out at something like $3 million/life.  This is pretty good value even at current breaker prices - airlines spend way more than that trying not to kill people, car companies too when they do safety recalls.  Once the breakers drop in price it'll be a very cheap way of saving lives.