Protecting Homes Against Wind 

Extreme winds, including tornadoes, are becoming a major concern for homes in Canada. Our country experiences the second-highest number of tornadoes globally. This puts houses at risk in one or more of the following failure modes: 

• Roof uplift: Strong winds generate an uplift on the roof, tearing apart shingles, sheathing 
• Window breaks: Flying debris penetrating unprotected windows
• Structural damage: Extreme winds tearing apart structural elements from walls and roofs 

… all of which can lead to:  

• Water damage after damage from strong wind leaves roof, walls or windows unprotected 

Homebuilders, developers, and renovators can help with more complex measures by: 

• Using stronger bolts to anchor structure to foundation, keeping it firmly in place  
• Covering exterior walls with durable sheathing, like plywood or OSB 
• Securing wall and roof sheathing with more and stronger nails  
• Connecting upper and lower wall panels for better strength and stability against wind forces 
• Reinforcing gable-end walls by tying them back to the main structure 
• Using sturdy materials for gable-end walls, like plywood or OSB 
• Strengthening the roof-to-wall connection with special anchors or metal connectors 
• Using more and stronger nails along sheathing edges to prevent panels from being lifted  

How do I know if severe wind is a concern for my area? 

You can assess the severity of (normal) design wind conditions by consulting CHBA’s lookup tool for Appendix C of the NBC 2020.  In addition, you can find the likelihood of tornadoes for your area in the interactive tornado map (Northern Tornadoes Project - Event Dashboard). For potential future wind conditions based on projected global warming temperatures, values can be found in the design value explorer page for every location listed in the National Building Code’s Appendix C. 

Where can I find additional resources?