Freeze Season Checklist: Keep Your Sprinkler System from Becoming the Problem

You expect winter to be hard on roofs, sidewalks and boilers.

Your sprinkler system? That’s supposed to save the building, not flood it.

But every winter, we see the same scenarios play out: frozen pipes, burst fittings and valve rooms that look like a hockey rink.

Here’s a quick checklist to keep your sprinkler system doing its job even when temperatures drop hard.

What to Look For to Avoid Sprinkler Freeze-Ups

A quick walk-through can catch most freeze issues early before they ever become a problem.

• Cold valve room. If it feels like a walk-in freezer, that’s something that needs to be addressed ASAP. Valve rooms need consistent heat, not “it usually stays warm.”

• • Ice or frost on doors, pipes or valves. Ice anywhere near a sprinkler pipe is a flashing warning sign.
  • Vulnerable zones. Watch loading docks, stairwells, exterior walls, garages and unoccupied spaces. These are repeat offenders.

• Dry systems that aren’t really dry. Condensation or trapped water can freeze fast if the system isn’t properly pitched or maintained.

Sprinkler systems don’t need arctic conditions to freeze. Prolonged cold combined with still air and a little trapped water is all it takes.

What You Can Do This Week

A few small fixes right now can prevent a very large mess later on. Here’s what to do:

• • Verify heat in all sprinkler and riser rooms (don’t assume, check).
  • Confirm thermostats are working and set appropriately, especially in lower-traffic areas.
  • Inspect known cold spots and make sure insulation is intact.
  • Document impairments immediately if heat is lost or temps drop.

• Make sure your emergency contact list is current.

This is all boring stuff…until it’s suddenly very exciting at 2 a.m.

Winter Sprinkler Q&A

Q: What temperature should sprinkler rooms be kept at?

A: Generally, sprinkler systems should be kept at 40°F (4°C) or higher. Anything lower increases freeze risk, especially overnight.

Q: Can dry sprinkler systems still freeze?

A: Yes. Dry systems often contain residual water or condensation. If they aren’t properly pitched or maintained, freezing is common.

Q: Are freeze issues more common during extreme cold?

A: Not always. Many failures happen during moderate cold spells that last longer than expected, especially when heat drops overnight or during weekends.

Q: What should I do if heat is lost in a sprinkler room?

A: Treat it as an impairment. Document it, monitor temperatures and take action immediately. Do not wait for visible freezing.

Q: Is a frozen pipe always obvious?

A: No. Some pipes freeze internally before showing any external signs. By the time water flows, damage may already be done.

When to Call In Help

If you’re not 100% confident that:

• All sprinkler spaces stay heated
• Your dry systems are draining correctly
• Or you know where your freeze-risk zones actually are…

…that’s the right moment to bring in help, instead of calling for it when something actually freezes.

If you’re not sure where your freeze-risk spots are, we can help you map them before winter maps them for you.

NOTE: Codes vary by jurisdiction. When in doubt, confirm with your AHJ.