Hurricanes typically threaten the 18 states along the Atlantic Coast and Gulf of Mexico—from Texas to Maine. Besides injury and death, there is almost always millions, and sometimes billions, of dollars in property damage. But hurricanes aren’t the only storms driving high wind events. According to the 2016 CoreLogic Windy City Index, Nashville took the honors of the windiest city, while Tallahassee has the highest windspeed not related to a storm at 92mph. And one only has to look to Tornado Alley as further proof that wind can be a much bigger problem than rain.
Staying abreast of code changes, new technology and products help all of us in the building industry create more resilient, wind-resistant structures. Here are some of the best building practices to protect against high wind events that we’ve found for 2017:
- According to Norbord, taller wall panels can provide a continuous load path which helps the home to withstand shear and uplift forces during high wind events. Creating stronger wall systems and safer homes isn’t the only advantage of using taller wall sheathing panels; it also cuts air leakage up to 60% because all joints are on framing members and it eliminates the horizontal seam.
- Roofs with multiple slopes, such as a four-sloped hip roof, perform better under wind forces than gable roofs with two slopes. Gable roofs are common only because they are cheaper to build. Research and testing show that a 30-degree roof slope has the best results.
- Wind forces on a roof tend to be uplift. This explains why roofs blow off during high wind events. To combat uplift, we recommend nailing down sheathing with ring shank nails (est. $50-$100 materials) which substantially increase hold down strength. And seal all sheathing gaps with a premium acrylic (best) or butyl (good) tape. For a simple 2,200 sqft home, tape will cost about $250-$400.
- Aim for strong connections between the structure and foundation. Structural failure is often progressive where the failure of one structural element triggers the failure of another. Connections can be inexpensively strengthened.
- Roof overhangs are subject to wind uplift forces which could trigger a roof failure. In the design of the wind-resistant home, the length of these overhangs should be limited to about 20 inches.
- An elevated structure on an open foundation reduces the risk of damage from flooding and storm-driven water.
Should a storm occur, there are many ways to repair and/or mitigate damage while you wait for insurance companies, which are likely to be overloaded with claims.
As a builder or contractor, what’s the best advice you can share about high wind building or repair? Share it with us via Facebook or LinkedIn!