Baby It’s Cold Outside! Freeze Protection Basics: Protecting Job Sites before Cold Weather Arrives
As we move into winter, it’s critical to think ahead while the weather is still mild to ensure your construction projects, facilities, and even homes are protected from cold weather. While we’re all familiar with letting the faucets drip at home to keep pipes from freezing, most of us are less acquainted with how to keep something like a commercial fire suppression system from failing in the cold. Long-time Ross Group team member and estimator, Vince Adamek, gave us the basics on how to keep six of the most cold-susceptible systems from succumbing to freezing temperatures.
1. Domestic Water Lines
These are typically what we consider the “drinking water” lines; however they also include hose bibbs and, in some residential cases, landscape irrigation. Most incoming domestic water lines from the meter to the building are underground and come to the surface in an insulated location. On the other hand, outlets like hose bibbs must be protected, especially if they are not classified as frost-proof or freeze-proof. Irrigation lines oftentimes are controlled by a separate valve. If that is the case, the valve should be closed for the winter and the irrigation lines drained.
2. Process Water Lines
Process water lines are associated with large HVAC systems that provide heating and cooling to structures like a commercial office building. Due to how these systems function, multiple water lines will flow continuously from the primary source (chiller and/or boiler) to individual air handling units located throughout the building. In many cases, these lines flow through unconditioned spaces such as a mechanical room, above-space, or even outdoors. To help prevent freezing, glycol is added to the water, similar to adding anti-freeze to your car’s radiator. And just like your radiator, the glycol level must be checked and confirmed to ensure there is a sufficient level to help prevent freezing.
3. Fire Suppression Systems
Fire suppression lines are one of the systems most susceptible to freezing because they are almost always located in unconditioned spaces. Incoming lines are typically located in an unconditioned room on an outside wall of the building, and the distribution lines travel in unconditioned attic and above-ceiling areas. During last year’s stretch of below-freezing temperatures in the Tulsa area, there were numerous fire sprinkler line breaks that caused major property damage to many commercial and retail establishments. To prevent this from happening in the future, the majority of new construction projects are including sufficient heating in the room containing the fire sprinkler riser, and thermostatically-controlled heating units are being added to most existing rooms. Additionally, dry-pipe fire sprinkler systems are becoming more prevalent, as these systems are designed so the lines do not contain water full-time.
4. Temporary Water Tanks
Temporary tanks are used primarily to store/provide water to locations such as construction sites or remote locations where a permanent water source is not readily available. In most cases, they are located in an area where freezing will not cause significant property damage beyond the tank itself. However, it would definitely create a disruption in water provision, so the tanks need to be protected from freezing if possible. Ultimately, the best way to prevent a temporary water tank from freezing is to drain it during extreme cold conditions. However, this obviously eliminates the tank as a water source. If it is imperative to keep a temporary water supply during freezing conditions, a heated wrap/blanket can be used, or a heated enclosure can be constructed to house the tank.
5. Temporary Water Lines
Depending on the situation and how long temporary water service is needed, oftentimes temporary water lines will be run above grade or even simply lay on the ground surface, making them susceptible to freezing. Often these provide drinking water, or possibly irrigation water to establish new landscape, so they will likely need to be drained or moved underground to assist in freeze protection. If it’s a situation where the temporary line is exposed for only a few feet, you have the option to wrap it with insulation or electric heat tape to provide further protection.
6. Exterior Backflow Preventors
In most current commercial applications, domestic water supply backflow preventors are located in a “hotbox,” a buried underground vault that may be heated depending on the climate. However, most irrigation system backflow preventors are located above ground, especially in a residential application, and should either be drained and winterized or protected with insulation and heat tape during freezing conditions.
In many ways, freeze protection for construction sites and commercial facilities is very similar to freeze protection for your home. Because we can never be sure exactly when freezing weather will hit or if it will damage these systems, it’s important to be prepared. Knowledge of the climate in your area, along with awareness of how to handle freezing conditions, is key to making sure your home, facility, or job site is protected and ready for winter.