Preparing for Winter by Minimising Risks from Ice

Dear Member

As winter weather approaches, conditions can change quickly.

Freezing conditions can pose significant risks of damage to property as well as injury to members of the public, employees and volunteers.

Weather conditions during winter can cause severe property damage due to water ingress from frozen pipes bursting as the ice expands then thaws as temperatures rise again. It is important that employees and volunteers know how to thaw frozen pipes safely should they occur. This includes ensuring that they know they MUST NOT use open flame heat guns or heaters.

Snow and ice can also cause additional slip hazards particularly if access routes are not cleared and properly gritted. It is important that any emergency materials such as salt, grit, sandbags, fuel, antifreeze, tarpaulins are made ready, as well as emergency tools such as snow shovels, buckets and where appropriate cold weather clothing and boots.

Where reasonably practicable:

  • Before staff, volunteers and visitors arrive, treat paths and walkways with salt or grit before nightfall or early morning. REMEMBER that when clearing a pathway, clear the middle of the path first so that there is a safe surface to walk on.
  • Monitor the condition of the paths regularly, it is easier to move snow when it’s fresh and loose.
  • Never use water to melt ice and snow as it may refreeze and turn to black ice. Black ice increases the risk of injuries as it is invisible and very slippery.
  • When you are shovelling snow, take care not to block drains.

Pre-Winter Checklist

  1. Emergency use materials checked/replenished: tarpaulins, fuel, antifreeze, salt, grit, sand, sandbags etc.
  2. Emergency use tools checked/replenished: cold weather clothing and footwear, snow shovels, mops, buckets, squeegees, waste bags etc.
  3. Plans and tools made ready to isolate and drain down tanks, boilers, water pipes and sprinkler systems if temperatures drop excessively.
  4. Maintenance checks completed on owned emergency equipment (hand-held hot air guns, space heaters etc).
  5. Refresher training completed on the use of hand-held air guns/blowers to thaw water pipes plugged with ice. Employees and volunteers reminded that they MUST NOT use open flame heat guns or space heaters.
  6. Test all the external lighting around your building to make sure it is operating efficiently and safely. Adequate lighting is required for safety reasons.
  7. Book your boiler in for an annual service to ensure it is well maintained and operating efficiently.
  8. Whilst carrying out building maintenance checks, you should inspect the condition of your windows and window frames.

Protecting the Building Fabric

It is essential that the fabric of a building is not breached by collapsing roofs.

On roof areas such as flat parapet roofs, where melting snow cannot drain away, you should not allow excessive snow build up. If snow melt-waters cannot escape because of drains blocked with ice, the water will build up and overflow its normal containment channels to find a way into the building. On multi-level roofs where deep drifting of snow can occur, avoid allowing drifts to build up. The weight of ice and snow can cause a weak roof to collapse. Once inside the building, ice and snow will melt causing water damage. Once the building fabric has been breached, rain and snow can easily get in to cause yet more damage.

It is also important to keep the interior warm enough to prevent freezing. It is recommended to maintain temperatures at 4°C or more. Furthermore, maintain the loft space at a temperature as close as possible to the outside temperature so the ice and snow on the roof does not melt. This can be achieved by adequate insulation of the loft space and by increasing the flow of cold air passing through.

Checklist

  1. Rota set up for regular site inspections and internal/external building inspections by employees and/or volunteers during the freeze period.
  2. Ensure that water drainage channels at roof level are clear of leaves and other debris (this should include roof gutters, valley drainage channels, hoppers, parapet outlets and downpipes).
  3. Check that ground drains checked are clear of leaves, branches, waste and other debris.
  4. Risk of ice dam formation in roof level gutters checked: loft spaces re-insulated where internal temperatures found to be high enough to cause them to develop.
  5. Thermostatically controlled heating installed in freeze exposed areas of a building containing water tanks and water pipes. Includes loft spaces, attics, plant rooms and other isolated areas. Heating confirmed as able to maintain 4°C or more from floor to ceiling.

Water Systems

One of the most common causes of water damage is freezing pipes. As ice forms it expands and can cause pipes to burst. When the pipes thaw, water can escape and flow freely if the system has not been isolated.

You should locate and test the main water supply control valves to your building to ensure they can be closed and find and test any internal sub-divisional valves as well. Are all water pipes and tanks in unheated areas adequately lagged? If possible, unused, or non-essential water systems should be drained down prior to the arrival of freezing weather. Water leaks and burst pipes can be extremely destructive, especially if they go unnoticed for long periods of time. If the heating system stops working or makes a loud banging noise, then it could be a sign that a pipe is freezing. If that happens you should:

  • Turn off the water supply at the main stop tap
  • Contact an approved plumbing and heating engineer straight away
  • If your pipes freeze over, do not use open flame heat guns or heaters flame

Checklist

  1. Vacant or exposed areas with freeze history: drain equipment/pipes carrying water or susceptible to condensation or freezing. Antifreeze added to systems that cannot be drained. Make sure you check that any antifreeze used is appropriate for the equipment/pipes.
  2. Boilers, particularly drain lines, sight glasses and condensate lines, protected against freeze.
  3. Boilers not in use or not needed during the period of freeze have been drained down.
  4. Master water supply shut off valve to each building located and physically tested to ensure it can be closed. Sub-divisional valves within the buildings located and tested.
  5. Outdoor water filled equipment and tanks prone to wind chill have been shielded/lagged.
  6. Checked lagging and trace heating for indoor and outdoor exposed wet sprinkler pipework and valves.
  7. Space heating verified as functioning to maintain 4°C or higher for cold loft spaces, valve chambers and other isolated areas that have wet sprinkler pipework.

Sprinkler Systems

If your building has sprinkler piping, it is imperative that areas with sprinkler or firewater supply piping are protected against winter weather. This includes extra lagging, antifreeze, trace-heating or simply just maintaining room or building heating. Also, block up gaps in walls and doors to prevent freezing air reaching sprinkler pipes and valves. To ensure that winter proofing should not compromise the fire fighting capability of the sprinklers, fire pumps and fire hydrants please check with your sprinkler contractors. In extreme conditions, it may become necessary to temporarily isolate the freeze exposed sprinklers. This must only be done under the strict supervision of a pre-planned fire control impairment permit and reinstatement must be done as soon as possible after the thaw begins.

Checklist

  1. Sprinkler systems normally switched to ‘air’ for the winter period done at planned Autumn visit by sprinkler contractor or done in advance of threatened freeze period.
  2. Sprinkler contractor has inspected and freeze proofed all fire pump houses, fire hydrants, fire system water tanks and the associated pipework.
  3. Pre-planned fire control impairment permit procedure is in place ready for emergency sprinkler system isolations if required, with Red Tags or Lock-Out Tags ready for use. Refresher training on the procedure done for sprinkler contractors and employees.