Garage Fire Detection [Archive] - Team Camaro Tech

: Garage Fire Detection


Eric Kammerer
Dec 13th, 06, 08:59 PM
Well, after watching my neighbors' house burn nearly to the ground yesterday when his late model Regal sedan caught fire and took the garage and 2/3 of the house with it, I am looking for suggestions on what I can do to add some form of fire detection to my garage.

I have a 20' x 20' garage which is immediately under the master bedroom. I wanted to build a detached garage, but with the setback requirements I really can't do that.

I have correct fire extinguishers in the house and garage, all readily accessible. I store what little volume of flammable liquids I keep in the garage in a metal cabinet. The garage is finished with fire rated drywall.

What I need is an alarm that will be appropriate for a garage and louder than all get out so it can be heard all through the house at any hour. If my neighbors' fire had been in the middle of the night instead of early evening, they'd probably have overcome by smoke and fumes before the house smoke detectors were triggered.

I have been doing some research, and it looks like the common off the shelf smoke detectors (either ionization or photo sensors, or both) are less than ideal for a garage. I have found heat detectors at Grainger, but don't know much about them.

So, I just wanted to ask around and see what others with residential garages are doing to detect a fire. The way I see it, I have two choices:

- smoke detector that I have to disconnect when I am creating dust or other simple things that cause false alarms

- heat detector

Can anybody share other options? If a heat detector is the way to go, I'll just have to learn more about how to install them.

I'm not sure I will get a good nights sleep again until I get something in.

Mark C
Dec 13th, 06, 09:26 PM
Heat detectors are the only way to go. Photoelectric and ionization detectors will probably go off everytime you drive in or out of the garage.

Heat detectors are nothing more than a normally open contact held open by a bit of low temperature melting metal alloy. You can get 135, 155, or 195 degrees F. 135F would be appropriate for a garage. Detectors are listed for spacing anywhere from 15 feet to 75 feet with most rated around 50 foot spacings. Spacing mostly depends on whether they are fixed temperature and/or rate of rise detectors, with the lower temperature ones being listed for the larger spacing. One detector in the center of the garage would cover all but the largest of garages. You will need an alarm panel to use heat detectors, which will also drive your alarm sirens or horns. Any panel that can accept a normally open contact will accept heat detectors as an input.

Of course most residental alarm panels are not UL listed for fire alarm use, but for the most part the local authorities don't usually mandate that they be listed.

68rs406
Dec 13th, 06, 10:45 PM
Ditto to what Mark said, use a 135* heat detector in the garage, then you will get no nuisance alarms which are dangerous themselves, it gives you the "boy the cried wolf" syndrome, you won't take the alarm serious.
One thing I will add, since the shop is attached to the house, you should have an alarm, but an alarm is a life safety device only, while thats definately needed esp. in your case, consider looking into a sprinkler system as well. While an alarm saves your life, a sprinkler saves your property, although obviously secondary to your life, definately a concern.
Just use a "wet" system (always under water pressure) with a 135* head, in conjunction with an alarm, and you really are protected from total loss.
I install fire alarms in buildings as an electrician, so I have experience with that, but I actually discussed the whole sprinkler deal with a sprinkler fitter I worked with. He said it's a great idea (for the reasons I mentioned) and he's done a few in homes in fact, on the side. The head (water) pressure in a home is plenty sufficient, and the whole job is fairly simple, it's something I plan on having done eventually myself.
Just something to consider.

WildBillyT
Dec 13th, 06, 10:51 PM
Ditto to what Mark said, use a 135* heat detector in the garage, then you will get no nuisance alarms which are dangerous themselves, it gives you the "boy the cried wolf" syndrome, you won't take the alarm serious.
One thing I will add, since the shop is attached to the house, you should have an alarm, but an alarm is a life safety device only, while thats definately needed esp. in your case, consider looking into a sprinkler system as well. While an alarm saves your life, a sprinkler saves your property, although obviously secondary to your life, definately a concern.
Just use a "wet" system (always under water pressure) with a 135* head, in conjunction with an alarm, and you really are protected from total loss.
I install fire alarms in buildings as an electrician, so I have experience with that, but I actually discussed the whole sprinkler deal with a sprinkler fitter I worked with. He said it's a great idea (for the reasons I mentioned) and he's done a few in homes in fact, on the side. The head (water) pressure in a home is plenty sufficient, and the whole job is fairly simple, it's something I plan on having done eventually myself.
Just something to consider.

I worked in the enigineering lab of a fire spinkler company a few years ago. We found that more and more people are installing sprinklers in their homes. A 135 is perfect for this application, like you said. Should be an orange bulb.

BonzoHansen
Dec 14th, 06, 11:07 AM
My garage is attached too. I have considered getting a sprinkler setup. I am scared of fire. How can sprinklers be installed in an unheated space? Maybe a water recirulation setup?

Mark C
Dec 14th, 06, 11:39 AM
You need a preaction system. Basically a copressor keeps the line charged with air, until the sprinkler head blows off in a fire, at which point the decrease in air pressure allows your alarm valve (basically a check valve with an air chanber above it holding it closed) to open and water will then flow through the sprinkler head to the fire. They would be a major hassle in a residence as they require maintenance, an alarm panel (you do want to know when the water is flowing into your garage and an air compressor.

WildBillyT
Dec 14th, 06, 11:51 AM
My garage is attached too. I have considered getting a sprinkler setup. I am scared of fire. How can sprinklers be installed in an unheated space? Maybe a water recirulation setup?

Like Mark said, you can use a dry system like they do in cold climates and in some warehouses. Probably not cheap, and maintenance is required.

68rs406
Dec 14th, 06, 12:52 PM
Yes, a dry system would be a bit much hassle for a garage. But how cold does it really get in your space? If it is subject to freeze, you could use heat trace on the pipes, not a common method but how much pipe would really be in a garage space? Something to consider.

J Meadows
Dec 14th, 06, 03:09 PM
I have a friend who bought a house here in town that had been built by a fireman and he installed a wet sprinkler system. He also uses his garage for his business. It’s under the house. He has a hired man that works there 8 hours a day. Well the hired man left for lunch and when he returned he seen water coming out from under the garage door. A sprinkler head had broken and the water and saturated the sheetrock on the ceiling and it fell down on his motor home. He said that when he bought the house he asked his insurance agent about a fire insurance break because he had the sprinkler system but they told him that it was offset because of the potential water damage from a broken sprinkler heads.
Just another thing to consider.

kcs
Dec 14th, 06, 06:15 PM
You need a "dry" sidewall sprinkler head. It is a wet sprinkler system, water is in all of the pipe, and you install a long head. It is compressed nitrogen in a lets say a 12" piece of pipe with a sprinkler head on it. There is a disc on the inside of it, the heated side, and when the head goes off due to a fire, the nitrogen releases and the water pushes the disc and water sprays out. The head goes off at 155 degrees also, not 135. The dry head installs on the wall by the ceiling from 4-6 inches down. They can be ordered from as little as a few inches long to several feet long. They are used in walk in coolers, freezers, garages, etc. My house is fully sprinkled. My family loves it. It's a safe feeling. I did it because I am a licensed journeyman sprinkler fitter in Minnesota. Sorry to bore you with sprinkler 101 but I hope I helped.

WildBillyT
Dec 14th, 06, 06:30 PM
You need a "dry" sidewall sprinkler head. It is a wet sprinkler system, water is in all of the pipe, and you install a long head. It is compressed nitrogen in a lets say a 12" piece of pipe with a sprinkler head on it. There is a disc on the inside of it, the heated side, and when the head goes off due to a fire, the nitrogen releases and the water pushes the disc and water sprays out. The head goes off at 155 degrees also, not 135. The dry head installs on the wall by the ceiling from 4-6 inches down. They can be ordered from as little as a few inches long to several feet long. They are used in walk in coolers, freezers, garages, etc. My house is fully sprinkled. My family loves it. It's a safe feeling. I did it because I am a licensed journeyman sprinkler fitter in Minnesota. Sorry to bore you with sprinkler 101 but I hope I helped.


Heads can go off at different temperatures based on what bulb is installed.

I think it's something like:
Orange = 135*
Red = 155*
Yellow = 175*
Green = 200*
Blue = 286*

There may be a few more, that's all I remember.

kcs
Dec 14th, 06, 06:39 PM
Yes they do very in color and temperature. A residential head is a 155 degree head. I wish everyone had them in their house. You don't hear about the lives and property saved from sprinklers. You only hear of the deaths or the people jumping off their balconies. Blood sells on the news, not the good things in life! Just last month in Minneapolis at about 2:00 a.m. Some people left their apartment at about 1:00 a.m. for last call. They dropped their burning incense in the garbage and left. Fire went up the wall to the head in the bedroom. Head goes off and puts the fire out. Apartment complex held about 300 people. NEVER MADE THE NEWS!!!! Damn pager woke me up............ Happens daily, it never makes the news..........

WildBillyT
Dec 14th, 06, 06:41 PM
Yes they do very in color and temperature. A residential head is a 155 degree head. I wish everyone had them in their house. You don't hear about the lives and property saved from sprinklers. You only hear of the deaths or the people jumping off their balconies. Blood sells on the news, not the good things in life! Just last month in Minneapolis at about 2:00 a.m. Some people left their apartment at about 1:00 a.m. for last call. They dropped their burning incense in the garbage and left. Fire went up the wall to the head in the bedroom. Head goes off and puts the fire out. Apartment complex held about 300 people. NEVER MADE THE NEWS!!!! Damn pager woke me up............ Happens daily, it never makes the news..........

I agree.:beers: I'm happy that the industry is moving towards more residential-based systems.