drilling holes to mount a smoke detector in the garage?

[cwerdna]

Ok... two part question. I'm looking to mount a smoke detector in the garage.

Yeah yeah, it's not really advisable because of a combustion that might go on in there. The reason is because I began leasing a Leaf a week ago and because of my occasional charging @ home. I've only charged at all at home so far for 2 days, and only for a few hours. The rest of the time, I charged @ work (free L2 charging at work) and I today tried a free L2 public station for a bit.

At home, I'm just charging at 120 volts, but am paranoid in the event of overheated wiring or an outlet fire. Remember the PiP owner who had an outlet fire due to aluminum wire? (http://www.mynissanleaf.com/viewtopic.php?f=26&t=10887" onclick="window.open(this.href);return false

There's no aluminum wire at this house and the 120 volt outlet in the garage is on a 20 amp circuit. I charged for ~4 hours @ home yesterday w/o incident. Outlet doesn't get that warm, nor do the plug's prongs. (I've felt MUCH worse from electrical space heaters.)

The Leaf obviously has no exhaust and the Prius doesn't even fire up its engine until a few seconds after power on. Upon returning home, most of the time, the Prius' engine's off by the time the garage door even starts opening.

The other part is where to drill? Pics at https://picasaweb.google.com/105684180251177299188/Garage?authkey=Gv1sRgCIvfrteQn7OFeA.

I'm thinking of installing a smoke detector above the outlet near the ceiling. The L1 EVSE is plugged into the outlet.

Notice the nails in the wall? I figure that if I just put two screws into the wall vertically lined up inline w/the nails, I should be safe. There's a column of nails on the left of the 1st pic to the right of the door frame. The next column to the right starts 10 inches away. Then the next column is 12 inches to its right. Then, the next column to its right is 16 inches away. I don't know anything about typical residential construction standards and spacing (from the late 70s, if that helps. House was built in 1979.)

I don't have a stud finder and I found some interesting discussion/debate at http://www.dslreports.com/forum/r22072672-Finding-where-NOT-to-drill-through-drywall.

The right edge of the water heater is about 5 feet away from the outlet.

Anyone put in a smoke detector in a garage, esp. w/a gas water heater and find it causing false alarms?

 

[LeftieBiker]

Drill on the line of stud nails that has neither an outlet nor a switch on it, higher than the breaker box. And "downgrade" the breaker on the leaf's circuit to 15 amps, making sure there is nothing else on it that draws more than 100 watts or so..

 

[planet4ever]

There's a column of nails on the left of the 1st pic to the right of the door frame. The next column to the right starts 10 inches away. Then the next column is 12 inches to its right. Then, the next column to its right is 16 inches away. I don't know anything about typical residential construction standards and spacing (from the late 70s, if that helps. House was built in 1979.)

The standard spacing is 16", so that you have two studs supporting the middle of a 4' x 8' sheet if it is mounted vertically. (Yours were mounted horizontally, but the same spacing applies.) Obviously they were working from right to left, and got to the point where the next stud would be only 6 inches from the door frame. So rather than have 6" + 16" they moved the stud over to have 10" + 12". Actually, I believe the door frame needs a double stud, so 6" on center might have become 3" between studs, hardly enough room for the light switch.

Ray

 

[KillaWhat]

I'm an EE and used to design things, including really high end fire and intrusion systems.

In a garage, traditionally, you would be better off with a "rate of rise" heat detector than smoke detection.
If you do go with a smoke, I would be surprised if the gas hot water heater would set it off (and if it did you should get the heater looked at :roll: )

 

[scottf200]

At home, I'm just charging at 120 volts, but am paranoid in the event of overheated wiring or an outlet fire.

I'd just make sure you put a "hospital grade" outlet in. High quality - see this thread as an example: http://forums.mikeholt.com/showthread.php?t=126129" onclick="window.open(this.href);return false;
Google search for them: https://www.google.com/search?q=hospital+grade+20a+120v+(outlet+OR+Receptacle" onclick="window.open(this.href);return false


And make sure the wires are attached using the screws and not the quick-plugins in the back. Any extra resistance causes heat and break down.

 

[Nubo]

If you need to find studs, get a stud finder. 16 inches on-center gives you an idea of where to expect a stud, but it's not a guarantee.

But I don't think you need to use stud-mounting for a smoke detector. These are generally lightweight and can be mounted with "drywall anchors"; probably will be included with the unit.

As far as location, I'd follow the instructions that come with the unit.

 

[ebill3]

If you are asleep in a bedroom, will you hear an alarm in the garage?

I wouldn't, so I bought a package of two wireless alarms - one in the garage, the other near the bedroom. Most modern homes have interconnected alarms. If you have such, consider tapping into the system. I could not, as I rent.

Certainly agree on the water heater. If it triggers the alarm, there is a problem with venting the water heater and it needs to be taken care of.

 

[cwerdna]

If you need to find studs, get a stud finder. 16 inches on-center gives you an idea of where to expect a stud, but it's not a guarantee.

But I don't think you need to use stud-mounting for a smoke detector. These are generally lightweight and can be mounted with "drywall anchors"; probably will be included with the unit.

As far as location, I'd follow the instructions that come with the unit.

My concern about location has more to do w/not hitting anything that I shouldn't (e.g. wiring or pipes).

As for location, yeah, it has guidelines about not being in air dead space, being within 12 inches of the ceiling, etc. but does say to avoid garages (due to combustion products there, potential temperature extremes, etc.)

 

[LKK]

I have a smoke detector in my garage. The detector is really light and does not have to be screwed into studs, just screw into one of those expandable plastic inserts. The detector has a mounting plate, screw this into the ceiling which makes it really easy to install the detector, at least the battery powered dectector.

I decided to replace an existing 120 VAC smoke detector at the same time. New detectors come with a RF link so if one goes off it automatically sets off all the other smoke detectors connected to that link. So now I have a detector powered off of AC on the 2nd floor, a battery powered detector on the first floor and another battery powered detector in the garage, all communicating together via the RF link. If one goes off, all the others go off as well. The sound levels are so high it is impossible to sleep through it. This works for me as I wouldn't be able to hear the detector in the garage otherwise.

 

[FairwoodRed]

It wouldn't hurt to put a CO detector in the garage. Sometimes gas water heaters malfunction and you can get lethal levels of CO in the garage. Without a CO detector, you wouldn't know it until you were already in the bad air.

As for finding where not to drill, get a stud finder. Most of them also detect nearby voltage. Just exercise a little caution and faith when drilling your holes. Homes are supposed to be built so that all electrial and plumbing are at least 1.5" from the edge of the stud (centered in the depth of the wall) If they are closer then that, they are supposed to have metal nail plates on top of the studs to prevent you from easily drilling into the pipe or wire.

Every once in a while, your best preparations go wrong and you hit something. Wires make a big pop and sound scary, but the circuit breaker kicks in before serious harm is done. By the way, when working on electrical, don't use a metal ladder, keep one hand in your pocket, and have a safety watch person standing nearby to call 911 if it goes bad. Water pipes will leak all over the place, but some towels will clean that up easily. Make sure that you know where your water shut off it and that it works well. Sometimes you have to open a faucet because the shut off doesn't fully shut off. Probably the worst that you can hit though, is drain pipes. It can be hard to know that you hit drain pipes and you could be chasing a slight dampness that looks like a dog drooled. All the time the grey water is contaminating the back of the drywall.

Do you have a floor above the garage? Is it a bathroom or kitchen? Might be safest to mount the detector under a different room. Smoke detectors tend to detect earliest when mounted to the ceiling and away from walls. Many garages have a droped ceiling running thru the middle for the HVAC ducting. If yours do, then I recommend two smoke detectors, one for each half.

Smoke detector installation is an easy DIY project and with a stud finder, you should have little trouble.

 

[RegGuheert]

Anyone put in a smoke detector in a garage, esp. w/a gas water heater and find it causing false alarms?

It wouldn't hurt to put a CO detector in the garage. Sometimes gas water heaters malfunction and you can get lethal levels of CO in the garage. Without a CO detector, you wouldn't know it until you were already in the bad air.

Better yet, replace the fossil-fuel-burning water heater with a heat-pump water heater and eliminate that source of combustion gases and heat in your garage and replace it with a sink for heat which will keep your garage cooler during hot periods for the benefit of your LEAF. (If your garage gets below about 45F normally in winter, you may need to switch your HPWH to resistive heat during those periods.)