Pre-Season Cold Weather Preparations

Before winter sets in

The cold weather and frequent storms of a New England winter can cause serious damage to public buildings. Ice storms and heavy snow accumulations can bring down trees, utility lines, and communication towers, causing power outages, disrupting vital communications links, and frozen pipes.

How well are your municipal and school buildings prepared for winter exposure to freezing temperatures, wind, ice, sleet and snow? Exposure to these elements without proper precautions can lead to costly property losses and disruptions to municipal services and education.

Preparing for Winter Storms

Winter, and the freezing temperatures, snow and ice that it brings, is a significant hazard for CIRMA members. Add in power outages, slips and falls on ice, and heavy snow and your municipality or school looses can, well snowball.

Before Winter Arrives

• Before the first freeze, turn off and drain all outside water faucets and sprinkler systems.
• Make sure equipment, valuable items, or items that could be damaged are located where they will stay dry--off the floor and away from sources of water.
• Test the water shut-off valve; now is a good time to replace leaky or corroded valves.
• Fully insulate all water pipes, even PVC pipes, which can crack and break when frozen.
• Pay close attention to insulating sprinkler or water lines in
• unheated attics or dead air spaces,
• near outside walls and windows,
• pipes on the north side of buildings,
• areas exposedd to strong winds,
• concealed cielings and wall spaces, penthouses, and
• cooler areas such as entryways and bathrooms
• Winterize unheated, unoccupied, or vacant buildings. Even small leaks can cause extensive damage if left undiscovered for a long period of time.
• Test emergency generating equipment and battery back-ups.
• If you have generators, make sure they are properly rated for the job and are "good to go." Perform a startup test now. Ideally generators should be tested under actual load conditions quarterly. Make sure that you have fuel on hand; do not use gasoline or diesel fuel that is more than a year old. (Please see Hartford Steam Boiler Inspection and Insurance's guidelines for Preparing for an Electrical Power Outage for more information about testing and operating back-up generators.)

Prepare and Protect Staff

• Schedule regular building checks, or "Freeze Watches," during storms and cold weather.
• Schedule snow and ice removal of roadways and sidewalks. Ensure snowplow operators have atttended safety training.
• Provide staff a list of emergency telephone numbers. Include, for example, snow removal contact, HVAC repair, utility company, the weather bureau, and the Risk Manager.
• Have cold weather gear on hand. Hats, gloves, emergency blankets, flashlights and batteries will all be useful during a cold weather emergency. Make sure that the staff knows where they are stored.

During a winter power outage

• If your building does not have its own generators, make arrangements to obtain non-electrical heating units during emergencies
• Power surges and sags can damage equipment. Unplug them during severe weather or install surge protectors.
• Turn on the faucets to let the water trickle through to help prevent the pipes from freezing.
• Temporary or portable heating devices should only be used for facilities personnel for emergency purposes

Frozen Pipes

However tempting it is to turn down the building's thermostat to conserve fuel during cold weather--don't. The clean-up costs of fixing burst pipes is much more than the cost of the fuel saved. Thermostats should never be set lower than 55 degrees. Keep thermostats above 65 degrees when the weather may dip below 0 degrees or the facility is to be unoccupied for a weekend or longer.

During Cold Weather

• Keep all building areas heated, never lower than 55 degrees.
• Put low temperature alarms in place.
• Remove barriers to the flow of warm air, i.e., remove some ceiling tiles to allow air circulation.
• Maintain heating system.
• Ensure adequate fuel supply for heating system over weekends and vacations.
• Consider using UL or equivalent heat tape or similar products--but consult a professional about how to apply and use heat tape, as improper use can cause a fire.
• Drain unused water systems.
• Consider using antifreeze solutions in non-potable water systems.

During a "deep freeze," when temperatures drop below 20 degrees

• Schedule regular building "Freeze watches," during winter storms and cold weather.
• Turn thermostat to 65 degrees or higher.
• Open cabinet doors to allow warm air to circulate around plumbing pipes.
• Temporary or portable heating devices should not be used by the building occupants for supplemental heating. These devices should only be used for facilities personnel for emergency purposes.
• Let water trickle from faucets that are served by exposed or vulnerable pipes. Even a small trickle of water flowing through the pipe will help prevent it from freezing.

Thawing a frozen pipe

If a water pipe does freeze, it should be thawed immediately, but very carefully. Building fires have been started by careless people who've used a propane torch to thaw a pipe.

• Locate the main shut-off valve and be prepared to c lose it in case of sudden rupture
• Find the frozen area of the pipe; it may have frosted or have ice on it. If the situation is getting critical the pipe may be slightly bulged or look slightly fissured.
• Open the faucet closest to the frozen area.
• Aim the warm air from a hair dryer at the frozen area of the pipe to gently thaw it. Never use a propane torch. Pipes that heat up too quickly can rupture and burst. Worse, fires can be easily started by the open flame. You can also use an infared heat lamp, if the pipe is behind a wall.
• PVC pipes, as well as copper pipes, should be thawed as quickly as possible because they too can rupture and burst.
• Begin thawing from the faucet side, moving backwards towards the main water line; this allows the water to flow out, without adding further stress to the pipe.

Additional Discussion Notes: Areas of your building that have poor air circulation are likely to be much cooler than the room itself, causing pipes located there to freeze.

Snow Loading- Roofs 

Snow on sidewalks and roadways can cause slips, falls and auto accidents. Heavy snow accumulations on roofs are just as problematic. Roof damage from heavy snow loads and ice dams are a major cause of property loss. Worse still, a sudden roof collapse can seriously injure or kill occupants of the building.

How much snow can a roof hold? If the building is relatively new, the snow load rating may be found on the building plans. If the building is older, a profesional may have to be consulted. The fact that a roof has lasted through many snow storms does not guarantee that it will last through the next. Roofs of most older buildings were built with little or no insulation, so snow melted fairly quickly. If insulation has been added to the roof, snow and ice won't melt as rapidly and snow loads will accumulate to greater weight levels, further fatiguing an aging structure.

Estimating Snow Loads

Unfortunately, there is no easy way to determine how heavy a snow load is. The density of snow varies greatly. Freshly fallen snow is much lighter than thawed and refrozen snow. Dry, newly fallen snow may weigh 7-10 pounds per cubic foot; thawed and refrozen snow may weigh up to 60 pounds per square cubic foot. Rain water will add even more weight. Structural engineers recommend taking several cubic foot samples of snow and weighing them to calculate the weight of snow on a roof, rather than measuring the depth of the snow. Drifting snow, which may put excessive loads against equipment or penthouses or at walls between roof levels, will complicate calculations.

Signs of Danger

Fortunatley, few roof failures occur without some warning signs, beware of:

• Severe roof looks.
• Ripples or bends in steel roof supports. Also cracks in wooden members, rolled or bent metal purlins.
• Sagging ceilings or roof lines. Note: a suspended ceiling may hide these sags. Remove the tiles, and look above them.
• Cracks appearing in walls or ceiling. Again, a suspended ceiling may hide these cracks.
• Loud popping or cracking noises from the building structure. (A laminated wood beam in one school broke with such force that personnel reported hearing what sounded like a gun shot.)
• "Ponding" of water on the roof areas where it never accumulated before.
• Obvious deformities in the roof.

Remember, look for these warning signs during the annual structural insepction as well as during cold, snowy weather.

If a snow load is too heavy for the roof, the only solution is to remove it as quickly as possible. Snow removal plans are commonplace for roads and parking lots; consider developing one of your facilities' roofs.

One way to remove snow from a roof is to physically get up on top of the roof and push the snow off with a shovel and/or broom. This approach, obviously, poses serious safety concerns. It's important to use ladders, safety ropes, and take all necessary precautions. Snow rakes also can be used to remove snow.

When working from the ground using a snow rake, use extreme caution when working near overhead electrical power lines. Also, avoid excessive scraping on the roof or trying to chip off ice. This can damage the roof.

Roof Snow Removal

• Remove snow and ice from drains or drainage devices first.
• Remove drifted and unbalanced snow loads first.
• Remove snow in strip patterns, starting at the drainage device and proceeding up the slope. Remove snow in strips. The goal is to reduce the load: the snow and ice do not have to be completely removed.
• Take care when you remove snow at the base of walls.
• Use plastic shovels and plastic tubs for lowering the snow to the ground.
• Protect and barricade areas where snow will be dumped or lowered.
• Don't use snow blowers.
• Don't pile snow on the roof.
• Don't use picks, hammers, spud bars, or other sharp tools to remove ice.
• Don't use hot water pressure washers to remove snow from the field of the roof. This water generally freezes before it drains from the roof, adding to the weight.
• Don't block exit doors or fire exits with snow dumping or stockpiling.

Contact your CIRMA Risk Management Consultant to learn more about our risk management programs.