How to Prevent Commercial Fire Sprinklers from Freezing
Mineral fiber insulation is one of the primary ways to reduce the risk of sprinkler system from freezing. Although insulation alone may not prevent freezing when temperatures are cold enough for an extended period, properly installed insulation can significantly reduce the chance of sprinkler systems freezing.
A basic knowledge of heat flow will make clear how insulation is used to reduce the chance of sprinkler pipes freezing, according to the Insulation Institute.
How Heat Flow Works
Heat moves from warm areas to cold areas, and insulation slows the flow of heat. Insulation does not stop heat flow, so it is important that the pipes are installed in areas within or close to the heated part of the building and insulation is placed between the sprinkler system pipes and the colder outside.
Insulation’s property to slow heat flow is expressed as R-value. The greater the R-value the greater the ability to slow heat flow. It is important that the heating system remains on to supply heat to the building. If the heating system fails and the temperature goes below freezing for a long enough time the heat in the water will move to the colder areas and the pipes may freeze.
Another strategy to reduce the chance of pipes freezing is to use “heat tracing,” which is a flexible electric resistance heating element typically controlled by a thermostat, which is wrapped around the pipe to supply heat when needed, but this will not help when the electric power is out.
Options for Using Insulation to Reduce Freezing
Properly installed mineral fiber insulation is a practical method to reduce the chance of wet pipe systems (or those that always contain water) from freezing. Below are illustrations to show some possible designs for insulation systems for fire sprinkler systems which contain water. Note there are many other acceptable systems which will reduce the chance of sprinkler systems freezing and the systems shown are not guaranteed to prevent pipes from freezing.