Weather Safety Series: Is Your Flat Roof Prepared For Extreme Wind?

Mechanical room roof blown off to the lower level

As Canadians, we deal with rapidly fluctuating weather conditions year-round. Extreme weather fluctuations are on the rise, with over 1.3 billion dollars in weather-related insurance claims (including roof wind damage) being filed in Canada as of 2019, and while you may have a fair amount of warning for weather conditions like hurricanes, Northbridge Insurance’s research shows that it’s actually smaller severe weather conditions that create the most claims. If that wasn’t already a concern, in 2017 more than half of insured catastrophic losses in Canada were caused by wind events specifically. Even if you think that your roof is up to the challenge of a severe wind storm, it’s best to be prepared and have a professional inspect your premises.


The Increase of Extreme Weather Conditions

In the last 10 years, global weather conditions have seen a marked increase in storms, be it flooding, ice, rain, or wind. Architects and builders are taking notice, creating reinforcements for new construction builds that factor in these kinds of extreme shifts in weather. According to CPA Canada, climate change poses a unique issue for business owners, the core of it being how to protect their investments from inevitable spikes in severe weather conditions.


Extreme Wind Damage to Roof - Ontario, CA


What to look out for

When we inspect any roof, there are red flags that we look for in order to assess potential hazards from any sort of extreme weather condition. For wind concerns, your contractor should be noting if:

You have loose or missing metal copings or siding panels

Metal copings and siding panels have the potential to blow off with high winds. Loose copings and siding panels can become projectiles in a windstorm, and in turn a huge liability issue. If you currently have these items on your roof, have them inspected by a roofing professional once or twice per year in order to replace missing panels and/or re-secure loose sections, as needed.

If metal copings are something you are thinking of replacing, invest in the proper gauges and method of installation to avoid severe weather concerns. In our experience, we find that some buildings have light gauge aluminum siding on penthouses and vertical knee walls. Building owners may think that lighter materials will be less of a risk in the case of winds, but heavier gauge materials are a much safer alternative when properly secured. Therefore, ensure that the fastening method used is adequate for your circumstances.

Wood blocking is secured adequately

The air pressure fluctuates significantly at the parapet walls, therefore, if there is improper insulation attachment or wood blocking securement, then there is a risk of a blow off during severe weather. It is difficult to ascertain if this is at risk of occurring on your roof without a professional, which is why it is crucial to have routine inspections to ensure your building does not incur damage during wind storms, or any other severe weather condition.


Roofing damage from severe wind
Roofing damage from severe wind


Tie Up Loose Ends On Your Roof

Even though having a professional contractor inspect your roof is the gold standard, there are things that you can do to be better prepared for roof wind damage. One of the most dangerous risks on your roof, outside of structural issues, is inefficiently secured machinery or debris that has not been removed from your roof. Severe winds can cause these items to become projectiles during wind storms, which can cause serious damage to property and any people who are in their path. It’s a good idea to examine your roof periodically and clean up debris to ensure the safety of your building and those around it.


2022 Extreme Wind Damage to Roof - Ontario, CA


Make sure your deck substrate materials are appropriate for your property

When your contractor is designing your roofing system, there are design protocols that need to be followed. Factory Mutual has an extensive list of the specific requirements, but the broader requirements are:

  • Steel deck substrate – 22 gauge or heavier.
  • Structural concrete – minimum 2,500 psi.
  • Wood – 3/4-inch minimum fire retardant treated plywood, or minimum nominal 2-inch thick fire retardant treated dimensional lumber.
  • Cementitious wood-fiber, such as Tectum.
  • Lightweight insulating concrete.
  • Fiberglass-reinforced plastic.


Extreme weather can mean extreme stress for many of our building owners. At Elite, our goal is to mitigate that stress by preparing you for any and all weather conditions that may affect the health of your structure.

If you think your roof could use a checkup, feel free to chat with us using the chatbox on the right during business hours, or contact us here 24/7. Our goal is always to stop your roofing emergency before it happens. That’s the Elite Advantage.