Residential Sprinklers

[ScareCrow57]

I am looking at putting in an garage separate from the house. In this garage will be my workshop and the wood boiler for my home heat. Since this garage may not always be heated there is the possibility of freezing. So as I consider my design I thought it will be simple and inexpensive to add sprinklers. Which has me now thinking about how are these set up to work in areas that may freeze. I know that in industrial settings they have dry systems that only activate when there is a call for water. These must be hooked to air compressor and a supply of air must be there to keep the valve shut.

So tell me, how are residential systems set up to work in attics and unheated spaces.

[WD6956]

I am looking at putting in an garage separate from the house. In this garage will be my workshop and the wood boiler for my home heat. Since this garage may not always be heated there is the possibility of freezing. So as I consider my design I thought it will be simple and inexpensive to add sprinklers. Which has me now thinking about how are these set up to work in areas that may freeze. I know that in industrial settings they have dry systems that only activate when there is a call for water. These must be hooked to air compressor and a supply of air must be there to keep the valve shut.

So tell me, how are residential systems set up to work in attics and unheated spaces.

The type of system that is pressurized with air is called a Preaction system. Compressed air keeps the sprinkler valves clapper closed. If a sprinkler head is activated, the air is released which allows the clapper to open and water to flow.

Preaction systems exists for residential use as well. That would be the solution to running lines in an unheated space. I have seen home built versions that simply pressureized the lines in the winter months with air. The will only work though if the sprinkler heads are not on drop lines (pendants). In other words, the sprinkler heads must be screwed in right on the supply pipe. The idea being is you do not want to have any locations where water can be trapped when the sytem is drained. A simple way to explain how that works is picture this...

The supply valve to that section of pipe is located in a climate controlled area not subject to freezing. At that shutoff valve is a drain valve that is the lowest point in the system. At the very end of the piping should be another drain valve although this valve does not have to be at the low point on the system. Prior to winter months, shut off the water supply to that section and drain the water out of the system using both drain valves. The upper drain valve at the end of the system will assure that all water drains out from the bottom. Now attach your air compressor at the lower drain valve and blow the remaining water out through the upper drain. Then close the upper drain and pressurize the system at least 40psi above the water pressure. Obviously you want a gauge for this. Once that is done, close the drain valve and disconnect the air supply. Then open the water supply. If you did it correctly and there are no leaks, the system is now charged with air and is freezeproof.

[RFDACM02]

Not all, in fact most "dry sprinkler systems" are not preaction. Preaction systems require another initiating device such as smoke detectors or pull stations to release an electrically controlled device on the water supply. Then the water can fill the pipe bu not flow until the head is fused by the appropriate heat.

I'm not specifically familiar with residential systems that are dry pipe, and have have mostly heard of glycol loops for areas that might freeze, which would require check valves to keep it separate from the typical water based system. The main reason this isn't a big deal is that residential systems are not normally designed for unheated attics or garages as they're not required in these not normally occupied spaces.

[WD6956]

Not all, in fact most "dry sprinkler systems" are not preaction. Preaction systems require another initiating device such as smoke detectors or pull stations to release an electrically controlled device on the water supply. Then the water can fill the pipe bu not flow until the head is fused by the appropriate heat.

Thanks for catching that, i was confusing the dry type system with Pre-action. The pre-action system are in fact triggered by a pull station or flame, smoke or heat sensor and many are wired to turn off once the flames are gone and then turn back on again if they return.

[DeputyChiefGonzo]

There are special heads designed for residential sprinkler systems that can be used in areas where there can be freezing temperatures.

[WD6956]

There are special heads designed for residential sprinkler systems that can be used in areas where there can be freezing temperatures.

Those are just when the sprinklers themselves will be in an unheated space, like a garage. They are extended pendants that keep the water back int he non-feezing area till they discharge. They are used in walk in freezers as well. But the supply lines still need to be somewhere protected from freezing.

[DeputyChiefGonzo]

Those are just when the sprinklers themselves will be in an unheated space, like a garage. They are extended pendants that keep the water back int he non-feezing area till they discharge. They are used in walk in freezers as well. But the supply lines still need to be somewhere protected from freezing.

well.. no duh!

[WD6956]

well.. no duh!

At least we are all clear on that..

[FWDbuff]

So tell me, how are residential systems set up to work in attics and unheated spaces.

No, you tell us, since you know everything about anything else....Educate us, oh wise *** one.

[hwoods]

If your Wood Furnace is in the Garage, how is it unheated?.......

[WD6956]

If your Wood Furnace is in the Garage, how is it unheated?.......

I guess when the wood furnace is not running? I know many people use them as supplemental heat. Since they need to be stoked manually.

[nmfire]

I would think the vast amount of hot air in ScareCrow's head could not only pressurize a high rise dry system but also heat the space quite efficiently at the same time. I don't see why he needs all this fancy stuff.

[hwoods]

I guess when the wood furnace is not running? I know many people use them as supplemental heat. Since they need to be stoked manually.

My Son and daughter-in-law have one on their farm, But it's a Combination thing that, when the Wood Fire dies below a certain temp, an Oil Burner comes on, (in a separate Firebox) and maintains the water temps to the Heat exchangers in the house. When the Wood Firebox is stoked up again, the oil shuts down.

[ScareCrow57]

If your Wood Furnace is in the Garage, how is it unheated?.......

For those times when there is no fire (oil backup is in basement). Since it heats water an is insulated I don't know how much heat will be in the garage. This is a case of rather being safe than sorry

[ScareCrow57]

My Son and daughter-in-law have one on their farm, But it's a Combination thing that, when the Wood Fire dies below a certain temp, an Oil Burner comes on, (in a separate Firebox) and maintains the water temps to the Heat exchangers in the house. When the Wood Firebox is stoked up again, the oil shuts down.

Yea, I saw those. Of course I replaced my furnace about 5 or 6 years ago, so it is new and energy efficient. Imagine that, and improved more efficient furnace without government incentives.

[hammerhome]

You could also add a couple Cadet Heaters with a manual thermostat to your garage, keeping the thermostat set at the minimum which I think is 50f wouldn't cost much. The good ones have a fan in them that looks like a squirrel cage, more expensive but worth it.

Depending on where you live(and how cold it gets) you cold install pipe insulation around your pipes. You could also use wirsbo or pex style pipe that is not as fragile as other types(it can expand a lot).

Usually I recommend that if you have to put pipes in an attic space or unheated ceiling area that you "bed" them in insulation and wrap them with foam pipe wrap.

hope this helps..

[ScareCrow57]

You could also add a couple Cadet Heaters with a manual thermostat to your garage, keeping the thermostat set at the minimum which I think is 50f wouldn't cost much. The good ones have a fan in them that looks like a squirrel cage, more expensive but worth it.

Depending on where you live(and how cold it gets) you cold install pipe insulation around your pipes. You could also use wirsbo or pex style pipe that is not as fragile as other types(it can expand a lot).

Usually I recommend that if you have to put pipes in an attic space or unheated ceiling area that you "bed" them in insulation and wrap them with foam pipe wrap.

hope this helps..

Upstate NY and it gets into the high -20s or is that the low -20s? The heck with it call it -30F

[hammerhome]

i don't have any experience in that kind of temperature...keep the space heated! Well insulated and heated to a minimal temp would probably be your best bet, and fairly efficient when you factor the cost of replacing water damaged materials.

I would assume that even the main up into the sprinkler system(even if the system weren't charged) would freeze unless it were located someplace else. Good luck.

hh

[InsuranceLCRep]

ScareCrow 57

See NFPA 13D it has various options for you. I believe antifreeze will be the cheapest option for you. NFPA 13D has specific types and concentrations for the antifreeze as well as piping configurations. Keeping the main water feed before the antifreeze sections can be a problem, you may need to install heat tape or an electric heater for this area.

Do you have a good water supply in the garage? At least a 3/4 " line with about 60 psi? If not, a pump and tank may make this a very expensive install.

Consider an off site alarm for water flow, it can call your cell phone, etc. If the pipe breaks or you have a fire, you want to be notified. A local bell can work if you have anyone that will hear it and respond.

Garage doors will need sprinkler protection below the door rail guides. Install a side wall head on each door.

Some plastic pipe can be exposed, see the mfg cut sheet. Pex pipe can not be exposed. You may want to use copper or steel pipe if you do not plan to sheet rock the ceiling to provide a fire barrier between the pipe and the space.

Sprinklers near your boiler may need a higher temperature see NFPA 13D for what is needed.

Do you plan on designing the system or do you have someone that can help? After you review NFPA 13D you will see what is required. Keep in mind a 13D is for life safety and not property protection. Meaning it is designed to get you out. BUT 99% of the residential fires have been extinguished by 1 head, so most time it will also safe property.

How large of a garage do you plan on building?

Hope this helps.

[InsuranceLCRep]

Thanks for catching that, i was confusing the dry type system with Pre-action. The pre-action system are in fact triggered by a pull station or flame, smoke or heat sensor and many are wired to turn off once the flames are gone and then turn back on again if they return.

WD

Most if not all pre-action sprinkler systems do not turn off after the fire is out. They must be turned off by the FD or building occupant.

I have been inspecting pre-action sprinkler systems for 30 years and can count on one hand how many have been cycling on/off pre-action systems. You can not tell just by looking at the system if it is a cycling on/off pre-action system. You have to ask who ever installed the system how they programed the system to work. A hint is the type of detector used to set off the system. If it is cycling on/off pre-action system it will use restorable heat detectors. If you see a smoke detector it is not a cycling on/off pre-action system. Also if you see a heat detector it is not a cycling on/off pre-action system.

Hope this helps.