Necessary maintenance to protect your fire sprinkler system from winter weather
As the weather starts to turn colder, it’s an ideal time for building owners to turn their attention toward winterizing their commercial properties. Any systems that could be exposed to the cold, including sprinkler systems for fire protection, are particularly vulnerable.
Lack of proper maintenance is one of the leading causes of fire sprinkler system failures. If not properly maintained, these systems can freeze, burst, cause water damage, and fail to function in the event of a fire. That’s why it’s so important to ensure your fire sprinkler system is ready for winter and has been properly inspected, tested, and maintained by a qualified contractor in accordance with the National Fire Code of Canada (NFC), which references NFPA standard 25.
Most buildings have a wet sprinkler system (with water in the pipes), but in areas where you can’t maintain adequate heat, a dry pipe system may be used instead (which only has air in the pipes). Regardless, wet and dry systems both require proper maintenance to ensure they don’t freeze or rupture when the temperature plummets.
“The minimum adequate temperature for maintaining sprinkler systems in all buildings with water-filled pipes is 4 degrees Celsius, according to the NFPA 25. But I generally recommend keeping the building at around 10 to 15 degrees just to be on the safe side,” says Frank Cina, Manager of Risk Services at Northbridge Insurance.
Dry sprinkler systems
A dry system uses nitrogen or pressurized air to charge/monitor the system, so there’s no water sitting in the pipes; instead, if the system is activated, water is released into the system from the dry pipe valve. Dry systems are typically used in environments without heat, such as exterior loading docks, underground parking garages, and unheated warehouses.
However, there are still ‘wet’ components in a ‘dry’ system, where the water-filled supply pipe meets the dry pipe valve, which needs to be maintained at above 4 degrees Celsius. During the winter months, a dry system that’s improperly maintained could freeze or rupture. It could also freeze due to improper pitch of the sprinkler pipe.
As part of an annual inspection, a qualified contractor should drain the low-point or auxiliary drains of a dry system. But the building owner should continue to check and drain the system as needed; during freezing weather, it’s recommended to check the temperature in dry pipe valve rooms on a daily basis.
Wet sprinkler systems
In a wet system — the most commonly used sprinkler system for fire protection — pipes are filled with water and ready to activate in the event of a fire. But if they get too cold, they can freeze and rupture, causing extensive water damage. “The key here is to maintain adequate heat, even if workers aren’t around on a regular basis. But don’t use temporary heaters, because that in and of itself is a fire hazard,” says Cina.
Some wet systems use antifreeze to protect against freezing, but it’s important to test your antifreeze solution annually, before the onset of winter (as per NFPA 25, Section 5.3.4). Glycerin antifreeze can be used in both plastic (CPVC) and steel sprinkler systems, while propylene glycol should only be used in steel systems.
It’s also important to determine the required percentage of mixture based on NFPA standards (or use a premixed commercially available solution), limited to the minimum necessary for the lowest anticipated temperature. If antifreeze systems are not maintained at the proper concentration, they could, in fact, freeze.
Other areas of concern
Business owners should verify that any doors, windows, skylights, ventilators, stair towers, roof houses, unused attics, or other concealed spaces don’t expose piping to temperatures below recommended temperatures. “Frozen pipes can happen even in buildings that are properly heated — a condo where someone left the door open could result in a loss of hundreds of thousands of dollars,” says Cina.
In some cases, a building might lack adequate insulation in various nooks and crannies, causing drafts. “Sometimes we find that the way a pipe is routed on an exterior wall may not have enough insulation,” he says. “Usually you find out when you have a freezing issue.”
Pipe tracing or heat tracing — where cable is wrapped around a pipe that provides heating — is one way to help resolve this. Another potential option is to wrap insulation around the pipe in areas that are susceptible to freezing.
Specially designed sprinklers are also available for unheated areas such as walk-in freezers or exterior storage areas that are close to the building. For example, a dry pendent sprinkler extends from the wet system inside the building into the unheated area, with a seal that acts as a buffer where the wet system meets the dry system.
Have a plan in place
Building owners should consider having a plan in place if there’s a loss of power that causes the heat to shut off, such as during a major winter storm. This might involve draining your pipes, which could be costly — but it’s much more costly to repair the damage if your pipes freeze. With sensor technology, it’s possible to view a building’s thermostat via your mobile phone (and set alerts), so you’ll know if there’s a problem without having to step foot into the building.
Even if you lease the building, maintaining the sprinkler system could be your responsibility. Check your lease agreement or contact the building owner and obtain a copy of the inspection report. Annual inspections should be conducted by a qualified fire protection contractor, who will identify any deficiencies or maintenance issues. Inspection, testing, and maintenance must follow the requirements of the National Fire Code of Canada (NFC), which references NFPA standard 25.
Ensure your business is protected
Despite your best efforts, sometimes things can still go wrong. That’s when insurance can be helpful. To learn more about how a comprehensive policy can help protect you, your employees, and your bottom line, visit our business insurance page today!
