The Factors That Cause Wind Damage

Posted by Cherry Roofing

The Factors That Cause Wind Damage

Wind is a contributing factor to roof damage, which ultimately leads to roofing failure. Understanding wind damage can help you recognize early signs of it, and call your roofer for repairs before they become bigger ones. In today’s post, Mass-Tech Roofing and Building Co. shares how wind causes damage to roofing systems.

Uplift

Wind uplift is a phenomenon where the wind hits an exterior wall and forms a vacuum, creating suction on the roof surface and resulting in an upward force. The pocket of vacuum can be strong enough to lift asphalt shingles—particularly those that aren’t nailed down properly—and even tear them off the roof. Change in wind speeds also creates uplift because of the sudden reduction of air pressure due to change in wind direction. Both conditions can happen during a storm and is usually the cause of torn-off roofing more often than high winds hitting the roof directly.

Positive Pressure

Positive pressure is similar to uplift, in that damage to the roof is caused by wind hitting an object that offers resistance. It could be an exterior wall, a fascia board, or a steeply-sloped roofing plane. When this happens, shingles can be lifted from the edges, which results in tell-tale horizontal creases about an inch below the edge of the shingle above it. This is why a relatively new roof has adhesive under the shingle edges: in addition to reducing water infiltration, adhered shingles also protect the roof from the effects of positive pressure.

Missiles

Wind can also cause damage indirectly when it lifts objects like debris or stones and throws them to the roof, which, by definition, is a missile. On asphalt shingle roofs, this could result in damage that’s very similar to hail impact. Metal roofing systems can get dented or punctured, while tile and slate can get shattered upon impact. A roof with a high impact rating is less likely to sustain major damage from such objects. We also recommend keeping the yard clean to reduce the number of potential wind-borne missiles.

Mass-Tech Roofing and Building Co. is your leading provider of roofing services. Give us a call at (781) 826-7663. You can also fill out our contact form to schedule an appointment for a roof estimate.