What is the general advice on placing smoke and gas (CO2) alarms. I have a wood stove, so obviously want early warning for chimney fires. Can a smoke alarm be in the same room? Are C02 alarms best placed in bedrooms (I understand they are best placed at ground level)? Many thanks
Smoke/Gas Alarm Placement
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orlimar105 said:
1) Welcome to hearth.com . . . this is a great place to ask questions, so ask away.
2) I cannot help myself so I will have some fun at your expense . . . but it is all good, clean fun. You may find it difficult to find a CO2 detector . . . and if you do find one you will most likely find that the best placement for it will be in the refrigerator . . . next to the soda pop.
A common mistake . . . CO2 = carbon dioxide (usually a good thing . . . for carbonation, some extinguishers, etc.) vs. CO = carbon monoxide (nearly always a bad thing . . . namely cause it can cause you to die.)
3) And now the serious answer . . . I generally recommend not placing smoke/CO detectors too close to woodstoves even though it may seem contradictory to say so . . . placing them too close can cause too many false alarms which "desensitizes" the family into thinking that the alarm they hear at 1 a.m. is just another false alarm. You can place them in the same room (and I am sure folks will chime in here that they have done so and have had zero issues), but most folks say that doing so can often lead to lots of false alarms . . . the possible exception being a large room.
For this reason I recommend placing these detectors in the room adjacent to the room with the woodstove (the NFPA --and myself for the record -- recommends smoke detectors in the bedrooms, on every floor and in the hallways. That said, as long as your smoke detectors aren't placed in poor locations (i.e. close to dryers, woodstoves, furnaces, the kitchen, bathroom, etc.) there is nothing wrong with having more detectors vs. not having enough -- just make sure they're working and replace them every 10 years. In my house there are smoke detectors in every bedroom, in the downstairs and upstairs hallways and in my mudroom which is adjacent to the kitchen . . . false alarms are very rare . . . unless I've burned something in the oven and filled the house with smoke.
CO detector placement is typically in the hallway near the bedrooms (although some folks -- and CO manufacturers coincidentally enough -- also recommend placing a CO detector 10-15 feet from the most likely CO producing appliance.) Once again, there is nothing wrong with having more CO detectors than the minimum recommended as long as they are not located in areas which may lead to false alarms (i.e. in the garage) . . . so yes, placing them in the bedrooms if you are so inclined certainly isn't a bad idea . . . but normally folks place them in the hall outside of the bedrooms.
In your case . . . if you're looking for a little bit extra and early warning, but don't want false alarms and if the room with the stove is large you could probably get away with placing the detectors in the room on the far side . . . as I have stated . . . placing the detectors too close will inevitably result in false alarms since even the most skilled person will occasionally have some smoke "spillage" while loading the woodstove or starting the fire.
Great advice from firefighterjake. Co is slightly heavier than air but will rise with the warm air in the house so at least half way up a wall, even better at ceiling level. Just follow instructions on the co meter. If you sleep with the bedroom doors closed, as fire safety recommends, you may want one inside and outside the door to be doubly safe.orlimar105 said:
Ed
Prevention is a must - so have a look at this
http://www.cas4.com/Wood-Stove/Woodstove-Control-001.htm
Thanks
http://www.cas4.com/Wood-Stove/Woodstove-Control-001.htm
Thanks
colebrookman said:
Actually CO is slightly lighter than air
http://chemistry.about.com/od/howthingswork/a/codetectors.htm
Quick google search also bring up numerous pages supporting this.
To the OP
Code requirements in new houses require a smoke detector in each bedroom, within 10' of each bedroom door, and at least one on every floor. Co detectors are required 1 on every floor. Optional in MA is a heat detector in the garage or attic.
I burn in an Alderlea T-whatever the big one is. 1 smoke detector 6 feet from where the vent penetrates the ceiling. Another 12 feet from it 180 degrees opposite. If you've got a proper, insulated chimney of the right height and an air tight stove, you should almost never have smoke in your house.
I think putting the alarm in another room is a HUGE mistake. If your stove starts melting or somebody put something on the stove and it's going up, you need to know NOW, not in 4 or 6 minutes when smoke has formed thickly enough to fill the stove room and then begin filling the room next to it.
Install the detector close to the stove, and then, if you get too many nuisance trips, move it incrementally away.
Fires spread EXTREMELY quickly. You can go from stove top flame up to House-is-burning-down-get-out flames in less than a few minutes.
If you have too many nuisance trips, you don't have enough draft or you have an old stove - fix the draft or get a new stove.
As a final matter, I have almost zero concerns about CO. CO is formed as a product of incomplete combustion. But the stove is under negative pressure - a lot of it if you've got it set up correctly, and the only way CO is going to move out of the firebox and into the house is if your vent stack falls apart or becomes completely blocked - at that point, carbon monoxide is the least of your problems, and your smoke detector is going to trip much sooner than your CO detector.
CO is a problem with natural gas. The reason that it's such a big problem for natural gas is because if venting is ever inadequate on a NG boiler/furnace, the NG just keeps coming in. The you get a situation where you have combustion products - mostly CO2, saturating the air around where the NG is burning. So incomplete oxidation occurs, and you get CO.
A wood stove is substantially different. Unlike a NG boiler/furnace, a blocked vent will cause a stove to run poorly and you'll know it - smoke puffing, poor burning, etcetera. With a NG unit, there is no warning. It seems to be heating fine. A NG unit doesn't care if it's venting into your house or up through the stack.
A wood stove (air tight), can't vent into your house without completely smoking you out and/or causing a fire first.
So, put the CO detector in if you've got the 50 bucks and the worry.
But for curiosity, try to find a stat on how many people have been CO poisoned by an EPA wood stove installed in the manufacturer's manner (hint - none).
I think putting the alarm in another room is a HUGE mistake. If your stove starts melting or somebody put something on the stove and it's going up, you need to know NOW, not in 4 or 6 minutes when smoke has formed thickly enough to fill the stove room and then begin filling the room next to it.
Install the detector close to the stove, and then, if you get too many nuisance trips, move it incrementally away.
Fires spread EXTREMELY quickly. You can go from stove top flame up to House-is-burning-down-get-out flames in less than a few minutes.
If you have too many nuisance trips, you don't have enough draft or you have an old stove - fix the draft or get a new stove.
As a final matter, I have almost zero concerns about CO. CO is formed as a product of incomplete combustion. But the stove is under negative pressure - a lot of it if you've got it set up correctly, and the only way CO is going to move out of the firebox and into the house is if your vent stack falls apart or becomes completely blocked - at that point, carbon monoxide is the least of your problems, and your smoke detector is going to trip much sooner than your CO detector.
CO is a problem with natural gas. The reason that it's such a big problem for natural gas is because if venting is ever inadequate on a NG boiler/furnace, the NG just keeps coming in. The you get a situation where you have combustion products - mostly CO2, saturating the air around where the NG is burning. So incomplete oxidation occurs, and you get CO.
A wood stove is substantially different. Unlike a NG boiler/furnace, a blocked vent will cause a stove to run poorly and you'll know it - smoke puffing, poor burning, etcetera. With a NG unit, there is no warning. It seems to be heating fine. A NG unit doesn't care if it's venting into your house or up through the stack.
A wood stove (air tight), can't vent into your house without completely smoking you out and/or causing a fire first.
So, put the CO detector in if you've got the 50 bucks and the worry.
But for curiosity, try to find a stat on how many people have been CO poisoned by an EPA wood stove installed in the manufacturer's manner (hint - none).
seige101 said:
You are absolutely right about CO being slightly lighter than air, in a laboratory with pure CO. Pure CO has a density of 28 while air has a density of 29. But in the real world Co is only one of many gases given off when fuels burn. They are now finding that many people, firefighters and residents are dying of cyanide poisoning and not CO as once believed. Our residences are loaded with cyanide producing material, which ,until recently, we never tested for. As we all know most people die not from burns but from the off gassing of burning materials. Long story short, buy and use the smoke and CO meters as per directions, they do save lives. Be safe.
Ed
I bought this house with only one detector, it is a new englander (considered a 1 and 3/4 story by realtors) I now have a detector at the top of the cellar stairs, one at the top of the main staircase and one in the kitchen as it is connected to the house by one normal size doorway. we get many false alarms in the kitchen but have it mounted so that the cover stands open when the battery is disconnected so it will be noticed (hopefully)
the detector at the top of the cellar stairs has let me know the few times my furnace has let smoke out ( the screw on one cover to the fire box is stripped.) the upstairs one has never sounded. I found having the detectors at the top of stairwells where heat rises gives a good location.
the detector at the top of the cellar stairs has let me know the few times my furnace has let smoke out ( the screw on one cover to the fire box is stripped.) the upstairs one has never sounded. I found having the detectors at the top of stairwells where heat rises gives a good location.
Frank
You seem pretty sure on the CO issue, but I believe you are giving bad advice.
Unless you have run a mechanical depressurization test on your home, while the flue is venting, you have no idea what is required to reduce the draft that your stove needs to maintain complete combustion. All it will take is the right set of combustion+atmospheric+mechanical+stack effect pressure forces to reverse that flue, and then you have a problem. And that problem may well be CO first - take this situation for example - a basement installed EPA stove in a 2 storey home. Stove is already in a negative pressure zone, especially if the air is being heated. Once coaling begins, flue will start to cool. Upstairs, as everyone gets ready for bed, Mom turns on the dryer (time of use electricity rates are a great way to save money), and Dad has a shower and turns on the exhaust fan. He plans on reloading the stove after the shower and heading to bed. As the flue cools, coaling (AKA pyrolysis) continues, until the flue reverses flow. No smoke, as there are only coals, and as the flue passes from positive vent to intake, the coals have incomplete combustion air, and CO forms.
Good thing they followed code requirements, and installed a CO detector.
There are many variables that affect draft, and draft affects combustion, and incomplete combustion can produce CO without smoke. Don't assume that your, or anyone elses, EPA stove and ideal set up means you can save even 50 bucks and not get a CO detector. Eventually, the forces of pressure will align, and you will have CO, or even smoke, enter your house.
You seem pretty sure on the CO issue, but I believe you are giving bad advice.
Unless you have run a mechanical depressurization test on your home, while the flue is venting, you have no idea what is required to reduce the draft that your stove needs to maintain complete combustion. All it will take is the right set of combustion+atmospheric+mechanical+stack effect pressure forces to reverse that flue, and then you have a problem. And that problem may well be CO first - take this situation for example - a basement installed EPA stove in a 2 storey home. Stove is already in a negative pressure zone, especially if the air is being heated. Once coaling begins, flue will start to cool. Upstairs, as everyone gets ready for bed, Mom turns on the dryer (time of use electricity rates are a great way to save money), and Dad has a shower and turns on the exhaust fan. He plans on reloading the stove after the shower and heading to bed. As the flue cools, coaling (AKA pyrolysis) continues, until the flue reverses flow. No smoke, as there are only coals, and as the flue passes from positive vent to intake, the coals have incomplete combustion air, and CO forms.
Good thing they followed code requirements, and installed a CO detector.
There are many variables that affect draft, and draft affects combustion, and incomplete combustion can produce CO without smoke. Don't assume that your, or anyone elses, EPA stove and ideal set up means you can save even 50 bucks and not get a CO detector. Eventually, the forces of pressure will align, and you will have CO, or even smoke, enter your house.
Firefighterjake
I have a 2 storey "forsquare" home, with the hall and stairway to the second level adjacent to the livingroom where our insert is. We are installing wired smoke (photo and ion) and CO detectors. My question is about installing the detector on the main level. As you discussed above, I want to avoid the false alarm issue, and so I want to install the dual smoke detector in the hall with the stairway. The CO detector will go in the room with the stove.
Are there any issues with being to close to the point on the ceiling where the ceiling becomes the wall of the stairwell? I'll post a pic of the space when I get home, but my concerns are that the hallway is small, and has a dead air space at one end, and that the direct path for air heading upstairs from the LR takes it thru a double wide doorway (no doors), so there is a dead air space in the hall above the doorway as well. Wiring the ideal spot is hard, so I am trying to optimise the situation.
Also, what about sloping surfaces, as in a rising stairwell?
I will have a dual detector and a CO detector on the ceiling in the landing upstairs outside the bedroom doors, so I have bedroom alarms covered at the minimum (not sure if I can get wired units into the rooms, but will check).
I have a 2 storey "forsquare" home, with the hall and stairway to the second level adjacent to the livingroom where our insert is. We are installing wired smoke (photo and ion) and CO detectors. My question is about installing the detector on the main level. As you discussed above, I want to avoid the false alarm issue, and so I want to install the dual smoke detector in the hall with the stairway. The CO detector will go in the room with the stove.
Are there any issues with being to close to the point on the ceiling where the ceiling becomes the wall of the stairwell? I'll post a pic of the space when I get home, but my concerns are that the hallway is small, and has a dead air space at one end, and that the direct path for air heading upstairs from the LR takes it thru a double wide doorway (no doors), so there is a dead air space in the hall above the doorway as well. Wiring the ideal spot is hard, so I am trying to optimise the situation.
Also, what about sloping surfaces, as in a rising stairwell?
I will have a dual detector and a CO detector on the ceiling in the landing upstairs outside the bedroom doors, so I have bedroom alarms covered at the minimum (not sure if I can get wired units into the rooms, but will check).
We've had alarms since the early '70's and always put 'em by the bedroom cause that's what the directions said back them. And even thought we've been through many alarms...that was the last time I read the directions and the alarms are still by the bedrooms.
Hell if you're up and not sleeping you wouldn't need an alarm to tell you got a smoke issue, with CO yes...but those alarms are so piercing they sound of all through the house.
Hell if you're up and not sleeping you wouldn't need an alarm to tell you got a smoke issue, with CO yes...but those alarms are so piercing they sound of all through the house.
rowerwet said:
Just a suggestion . . . I would move the smoke detector in the kitchen -- if you are truly concerned about this area but would like to avoid false alarms try moving it to the room adjacent to the kitchen and see if this reduces the number of false alarms (well in reality false positives). I might also suggest changing out the detector from an ionization detector (the most common detector found in homes and also a detector that is notorious for false alarms from cooking issues) to a photoelectric detector.
I would not continue with the practice of pulling out the batteries or disconnecting it . . . mainly because I have the belief that false alarms should not be a common occurrence if the right type is selected for the need, the detectors are placed in the proper locations and folks utilize the most modern features (i.e. hush features built in to many newer detectors). Folks with many false alarms eventually get used to the false alarms and begin to associate the alarm as just another false alarm -- nothing to get alarmed over . . . even if that alarm is occurring late at night.
savageactor7 said:
I think I may be reading this wrong . . . I'm assuming that you have since replaced these detectors over the years and you're not using the very same detectors you bought in the early 1970s, right? Many people do not realize that smoke detectors should be replaced every 10 years (and of course battery operated smoke detectors should have their batteries changed 1-2 times a year.)
oconnor said:
I'm very much a visual learner so I'm not quite sure of what you're looking at (pictures would help) . . . but I am confident in saying that smoke detectors should not be placed in the space where a wall meets the ceiling as folks much smarter (and better paid than me) have said that smoke detectors on a ceiling need to be placed at least 4 inches away from the wall (and if mounted on the wall they should be placed 4 inches below the point where the wall meets the ceiling) since a dead air space can form due to the nature of smoke.
Frank . . . I mostly agree with you. Ideally, if a woodstove and chimney are set up properly there rarely should be smoke and/or CO in the living space . . . but things aren't always ideal and, well, some folks don't always do the right thing or know what they're doing is wrong and yet if they don't know better they will think what they are experiencing is normal (i.e. years ago I lived in a camp and the chimney wasn't drafting properly and as a result every time I went to reload the fire there would be some residual smoke spill out . . . now I know this was due to a drafting problem, but at the time I figured it was just a part and parcel with heating with wood.)
I still believe that placing a smoke detector one room over from the woodstove is adequate . . . but as I noted it is also OK to place the detector in the same room providing it is large enough and/or there are few to no false alarms. I particularly like your commonsense approach to placing a detector in the room and then moving it a few feet away or into the next room if there is a problem.
As you also mentioned CO should not be a problem in most cases with a woodstove, but again the variables (as mentioned by another poster) can change and create a problem. One could say the same things about smoke detectors as they could about smoke detectors . . . i.e. You don't really need CO detectors or smoke detectors because a properly installed, vented and maintained woodstove should never lead to a CO problem or fire. The reality is CO is a real issue and could be a problem if the right chain of events (already mentioned) or one single catastrophic situation (i.e blockage in the chimney) presents itself . . . much in the same way that a fire could be a problem if the right chain of events (chimney not cleaned results in a chimney fire in a chimney that is unlined and has missing mortar between several bricks) or one single catastrophic situation (i.e. home owner installs the stove too close to combustibles) presents itself . . . even for the most conscientious woodburner.
For these reasons I highly encourage folks to install both smoke detectors and CO detectors. That said, I agree with you . . . I suspect that the number of folks succumbing to CO poisoning from woodstoves is pretty slim -- vs. the number of folks succumbing to CO from generators brought inside, car exhausts from cars left running inside an enclosed garage or cracked heat exchangers from NG, propane or oil (incidentally here in Maine we see far more cases of CO poisoning where folks have cracked heat exchangers in their oil furnaces since NG is still relatively new to this area.)
As I said I agree with a lot of what you say, but still maintain that the safest thing to do to protect one self and their family is to spend a little bit and get both smoke detectors and CO detectors. Incidentally, you can pick up a cheap (but half decent) CO detector from a reputable company (First Alert, Kidde, etc.) for about $20 -- not $50.
I still believe that placing a smoke detector one room over from the woodstove is adequate . . . but as I noted it is also OK to place the detector in the same room providing it is large enough and/or there are few to no false alarms. I particularly like your commonsense approach to placing a detector in the room and then moving it a few feet away or into the next room if there is a problem.
As you also mentioned CO should not be a problem in most cases with a woodstove, but again the variables (as mentioned by another poster) can change and create a problem. One could say the same things about smoke detectors as they could about smoke detectors . . . i.e. You don't really need CO detectors or smoke detectors because a properly installed, vented and maintained woodstove should never lead to a CO problem or fire. The reality is CO is a real issue and could be a problem if the right chain of events (already mentioned) or one single catastrophic situation (i.e blockage in the chimney) presents itself . . . much in the same way that a fire could be a problem if the right chain of events (chimney not cleaned results in a chimney fire in a chimney that is unlined and has missing mortar between several bricks) or one single catastrophic situation (i.e. home owner installs the stove too close to combustibles) presents itself . . . even for the most conscientious woodburner.
For these reasons I highly encourage folks to install both smoke detectors and CO detectors. That said, I agree with you . . . I suspect that the number of folks succumbing to CO poisoning from woodstoves is pretty slim -- vs. the number of folks succumbing to CO from generators brought inside, car exhausts from cars left running inside an enclosed garage or cracked heat exchangers from NG, propane or oil (incidentally here in Maine we see far more cases of CO poisoning where folks have cracked heat exchangers in their oil furnaces since NG is still relatively new to this area.)
As I said I agree with a lot of what you say, but still maintain that the safest thing to do to protect one self and their family is to spend a little bit and get both smoke detectors and CO detectors. Incidentally, you can pick up a cheap (but half decent) CO detector from a reputable company (First Alert, Kidde, etc.) for about $20 -- not $50.
firefighterjake said:
First time I read the directions was in the '70's...they said keep the alarms by the bedrooms cause 95% of fatalities were sleepers. Oh yeah we swap out alarms every couple of years...house dust mess's them up over time.
I reread my post, and did not understand it myself, so here is a picoconnor said:
Easiest install is the red circle, but I'm concerned with it being a dead air space. The green circle would also be easy, but not sure of the airfolw around it affecting it. Then Blue - more wiring thru an upstairs closet, and purple is going to be hardest to wire.
The stove is in the LR to the right of the pic.
Any suggestions as the best location for an ion/photoelectric deterctor?
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Where the blue dot is. Like you i would be concerned about lack of airflow in the red or green location.
savageactor7 said:
OK . . . I thought I read it wrong the first time . . . sounds good . . . for a while I was picturing you still using those groovy 1970s vintage smoke detectors that you bought over three decades ago.
oconnor said:
Gotta go with Siege on this one . . . Blue or purple spots would be my preferences . . . with Blue being the first choice for the ease of installation factor. The red spot might be OK, but I'm not a big fan of detectors on walls since it will take just that much more smoke to build up on the ceiling and bank down before activating a wall mounted detector . . . plus if you want the earliest detection I'm guessing smoke coming from the room with the stove or from the room down the hall would come out of the doorway, creep along the hall ceiling and then go right up the stairwell without banking down enough to set off the red or green spots.
I take it these are NOT going to be interconnected? I installed a funn interconnected smoke system last year, and just this year changes the basement and 1st floor with combo smoke/CO units, only to realize that when they sound off, if it is due to the CO alarm they will only sound other combo units, NOT the plain smokes in the bedrooms and 2nd floor hallway...
They will be interconnected units, but different config than mentioned earlier. Looking at Kidde Ion smoke/CO combo wired (talking actually) with a separate wired interconnected photo detector (not talking) that will activate the talking ion smokes. That will give me coverage on all three.
oconnor said:
Just keep in mind that if you have interconnected units, certain brands (maybe all?) will not sound a non co unit from a co unit... all the smokes will still sound though. Just food for thought. I had no idea when I replaced all my units, not I need to replace the one in the upstairs hall with a combo too, just so it will wake us up if the CO alarm is set off.
oconnor said:
Like I said, install a Goblin detector if you are afraid of Goblins as well.
Show me ONE case where a family was poisoned by CO from a wood stove. ONE. Let's start there. With the vast resources of the internet, if you can't find one concrete report of CO poisoning from a wood stove, then it's a non-issue.
If you can't find TEN cases, then buying a CO detector for a wood stove is a waste of money.
Ivy said:
Not going to bother googleing or arguing with you, however is the price of a life really worth saving 25 bucks? For me 25 bucks is extreemly cheep insurance for the what if circumstances.
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