Where sprinkler lines tend to freeze
Wet-pipe sprinkler systems hold water in the pipes at all times, so they rely on the building staying above freezing. Trouble spots include entry vestibules, loading docks, parking garage ramps, attic spaces in wood-frame apartment buildings, and areas near overhead doors or poorly sealed exterior walls. A heating failure over a holiday weekend can do the same thing to an otherwise warm space.
Dry-pipe and antifreeze systems are designed for cold areas, but they need regular maintenance. Water can collect in low points of a dry system, and antifreeze levels can drift. Mixed-use buildings along Denver commercial corridors, older warehouses converted to lofts, and newer podium apartment buildings with open-air garages all have places where these issues come up.
Sprinkler water usually starts clean but can pick up rust, sediment and anything sitting on the floors it crosses. In buildings with shared spaces, it may reach electrical rooms, elevator pits and storage units, which raises the stakes beyond a typical residential burst.
Order of operations for building staff
Confirm life safety
Make sure nobody is in danger from falling ceilings, wet electrical equipment or slippery stairs. Evacuate affected areas if needed.
Close the right valve
Shut the control valve for the affected zone, not the whole system if it can be avoided, so the rest of the building stays protected. Building staff should know which valve serves which area.
Make notifications
Contact the alarm monitoring company, the fire protection contractor, building ownership and the insurance carrier. Follow any fire department requirements for an impaired system.
Protect electrical and elevators
Have an electrician check wet panels and an elevator contractor check any pit or machine room that took water before equipment is used again.
Start water removal
Extraction and drying should begin quickly in every affected unit and common area, with moisture readings recorded for each space.
Restore and test the system
The fire protection contractor repairs the break, evaluates why it froze, and restores the zone to service.
Questions for the fire protection contractor and owner
- Why did this section freeze, and what will keep it from happening again?
- Is this area better served by a dry-pipe or antifreeze system?
- Are heat sources, insulation or alarms needed in the space?
- Which other zones have similar exposure?
- When will the system be fully back in service?
Points to remember
- Water volume
- Sprinkler flow can be heavy; shut the zone valve fast
- Fire protection
- A closed valve means reduced protection until repaired
- Who repairs
- A licensed fire protection contractor, not a general plumber
- Who dries
- A water mitigation company working unit by unit
General information for Denver, not a quote or professional advice. In an emergency, call 911.