Frost exclusions leave builders exposed to multi-million-dollar winter losses

In Canada, the fine print in builders' risk policies can determine whether a cold snap is an inconvenience or a multi-million‑dollar loss.

Most course of construction (COC) policies exclude damage from frost and freezing. That makes sense from an underwriting standpoint – these policies are designed to respond to accidents and unforeseen events, not to routine winter conditions – but it also means contractors and project owners can discover too late that a predictable weather event sits firmly outside their cover.

“The COC policy is meant to cover accidents and disasters,” said Brian Cane (pictured), construction program leader at Victor Insurance. “Cold weather and freezing are not accidents – especially not in Canada.”

That is where the precise wording around exclusions and any carveouts becomes critical. Not all frost and freezing exclusions are drafted the same way and, in practice, those nuances can dictate who ultimately absorbs the loss.

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Cane says some forms are absolute: any loss arising from frost or freezing is out. Others preserve coverage for “resultant damage.” In those wordings, damage to the item that actually froze (for example, a pipe) remains excluded, but secondary damage caused by the event (for example, water escaping throughout the project) can still be picked up.

He points to multiple Canadian claims where frozen pipes in winter led to “literally millions of dollars” in water damage on job sites. In those cases, insureds with resultant ‑damage carveouts had coverage for the broader water loss; those without such language would have been facing a large, uninsured hit.

False spring, cold snaps and complacency

The risk is not limited to deep winter. In Cane’s view, some of the most dangerous periods for construction projects are the shoulder seasons, when temperatures climb and risk perception drops.

As conditions improve in March or April, site teams can scale back temporary heat and fully charge plumbing systems, assuming the worst of winter has passed. A late‑season cold snap can then strike partially completed buildings where protections have been relaxed.

“I find that’s where people can get complacent,” Cane said. “They let their guard down because it’s been warm, and then you get a sudden cold snap when the plumbing system is charged.”

The result can be exactly the scenario frost and freezing exclusions contemplate: water lines rupturing in an unoccupied structure overnight, flooding multiple floors before anyone notices. If the policy contains an absolute exclusion and no resultant‑damage carveout, the entire loss may fall back on the contractor or owner.

Delays, shifting timelines and accidental exposure

Even where projects are planned around warmer months, delays can quietly change the risk profile. Jobs that were meant to begin and end in summer can drift into fall and early winter because of labour shortages, subcontractor issues or supply‑chain constraints.

“Conversely,” Cane noted, “your project that was supposed to be finished in the summertime extends into the fall,” which increases exposure to a cold‑weather event.

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That shift can create a coverage gap in two ways:

• The original risk assessment and budgeting may not have accounted for winter protection and monitoring costs; and
• The insured may not have focused on frost and freezing wording at placement, assuming the schedule would avoid low temperatures.

When delays push a project into November or December, both assumptions can quickly unravel. Without robust risk management and a policy that contemplates resultant damage, a late‑stage freeze event can turn into a significant balance‑sheet issue.

Keeping losses in check: heat, supervision and sensors

Cane stresses that policy language and project controls have to work together. Even with broader wording, risk management on site is still the first line of defence.

For frost and freezing, he highlights three practical measures:

• Maintaining adequate temporary heating in enclosed construction spaces throughout winter, and resisting the temptation to reduce it too early when temperatures fluctuate upward.
• Ensuring consistent, competent project supervision – Victor has seen inadequate oversight emerge repeatedly as a factor in large winter losses.
• Deploying automatic leak detection systems on suitable projects. These systems can flag unexpected water flow when nobody is on site and, in some configurations, automatically shut off the water supply, significantly reducing the scale of damage if a pipe bursts overnight.

“Those systems can really minimise damage,” Cane says. “If water is flowing when no one is there, that should trigger an alarm – and ideally, a shut‑off.”

Why specialist construction brokers matter

The complexity of winter risk and the differences in policy wordings underscore the value of specialist construction brokers in the Canadian market, Cane argues.

Construction insurance is a niche business, and brokers who place COC cover regularly are more likely to understand which carriers offer resultant ‑damage carveouts, how frost and freezing exclusions are structured, and when a particular project’s risk profile calls for pushing harder on terms.

“It’s important to make sure that the COC you use does provide that exception for resultant damage,” he says. Otherwise, contractors and owners can be “literally left out in the cold with millions of dollars of uninsured damage.”