Winterizing Fire
Sprinkler Systems
The Best Insurance is a Good Education



In climates that are subject to freezing temperatures, winterizing
is much more than a few checks before the weather turns
cold. Winterizing is an ongoing task that occurs throughout all
seasons of the year and affects the entire building system. Every
time a system is inspected or worked on, prevention of
upcoming freezing conditions should be a consideration. It
may be warm outside now, but at some point in the near
future, cold temperatures could create a risk of a damaged
system that will then not be ready to fight a fire, save a life,
and protect a property for our client.

Damage caused by a frozen system can create a long-lasting
situation where a system is out of service. The model building
codes and NFPA standards have done a good job of keeping
the legal responsibility of building and system maintenance
with the building owner, but we, as fire and safety consultants, have
an obligation simply as a good business practice to observe
possible dangerous conditions and assist our client in the
overall maintenance of the building. This can become an
opportunity to educate our client and assist in ensuring that
the building and fire sprinkler system are winterized properly.

One of the largest causes of frozen systems is poorly maintained
or disturbed insulation combined with a lack of
building heat. It is common for insulation to get pushed out
of place during a small building project. This can occur
during the simplest of minor projects such as an electrical
upgrade, a minor ductwork modification, or even a carpentry
change inside or outside the building. Any time that the
building insulation is changed, moved, or damaged, it is
recommended that a professional insulation contractor
become involved to observe the damage and make the
necessary repairs. Maintaining the insulation envelope and
appropriate vapor barrier is one of the most important
factors in the prevention of frozen piping. It is also critical
that we avoid accepting responsibility for the building
insulation system by trying to repair it ourselves. Remember,
the responsibility of maintaining the building and its systems
belongs to the owner. If possible damaged insulation is
observed, point out the deficiency so that it can be repaired
by the appropriate source. Documentation of this deficiency
is also important so that a paper trail is maintained, showing
that you have put the building owner on notice that a critical
situation may be present.

Periodic or annual inspections of dry-pipe systems and
antifreeze systems should be scheduled well ahead of
periods of freezing temperatures. It is critical that these
types of systems be properly maintained since they are
typically installed outside the insulation envelope in areas
where heat is not present. If possible, dry-pipe systems
should be tripped during the warm part of the season to
ensure that there is plenty of time for excess water to drain
out of the system. After a full system trip, it is not uncommon
for water to trickle out of the piping for quite some
time. Where low point drum drip type drains are present
within a dry system, it is important to continue draining
them until water is no longer present. This condition may
also occur throughout year as daily temperatures change,
creating condensation in the piping. It is important to
advise the owner’s representative on the procedure and
importance of draining low point drains so that they can be
maintained properly. As freezing temperatures approach, it
is important for the owner’s representative to perform
additional checks of low point drains to ensure that the
system is ready for the upcoming period of cold weather. As
temperatures dip below freezing and then rise above
freezing during daytime hours, it may be necessary for the
building owner to continue to monitor low point drains
until the risk of freezing temperatures has passed.
In addition to dry-pipe systems, we often find antifreeze
systems in areas subject to freezing. Proper levels of antifreeze
solution are critical to ensure that the system is protected. As
with dry-pipe systems, the level of antifreeze solution should
be checked and maintained well in advance of freezing
temperatures. The National Weather Service records should
be reviewed to determine the expected low temperatures for
the area and the level of antifreeze solution should be mixed
accordingly. Since antifreeze solutions are typically heavier
than water, it is advisable to mix the solution considerably
stronger than needed as major portions of antifreeze will
likely settle to the low points of the system. The good news is
that heat rises and the low points are likely to be the most
vulnerable portions of the systems. NFPA 13, Standard for
the Installation of Sprinkler Systems, provides guidance on
mixing and minimum levels of antifreeze solutions.
Drains that discharge to outside should be checked to ensure
that the drain valve seats properly and does not continue to
drip. In cold temperatures this can result in a dangerous
situation where drains discharge onto sidewalks or parking
areas, causing a slipping hazard. Additionally, leaking drains
can result in an ice plug, which may cause piping to rupture
and become unusable. Assuming that the valve is located
within the heated space, this is not necessarily an immediate
threat to the operation of the system, but will create a maintenance
problem later and could result in water damage caused
by the ruptured piping.

One last thing to consider is heat tape. Although not typically
considered as good freeze protection for fire protection
systems, occasionally we encounter heat tape and it is
important to ensure that it is in good working order. If
present, heat tape should only be used on bulk piping, drain
piping, or similar conditions where sprinkler heads are not
attached directly to the piping. A visual inspection of heat
tape should be performed to look for any damage that may
be present. Heat tape should also be checked electrically to
ensure that it is actually working and is ready to protect the
exposed piping. If you are unsure if the heat tape is operating
properly, advise the owner that a certified electrical contractor
should look at the situation and verify that it is operating
properly. Remember, maintaining the building systems is
ultimately the owner’s responsibility and liability. If heat tape
is used for protection of isolated piping, it is highly recommended
that monitored heat tape is used so that, in the event
of a failure, the owner is provided with notification that there
is a potential issue.

The best insurance for protection against frozen sprinklers and
piping is good education. Educating a building owner on the
importance of winterizing, maintaining a proper insulation
envelope, and providing adequate heat is one of the most
important tasks we can perform with regard to winterizing. A
well-educated building owner can provide the basis for good
maintenance which in turn provides for a system that will
continue to operate for years to come.