How Can Nashville Metal Roofs Resist High Winds?Mar 30, 2019
Metal roofs provide many benefits to a home, including resistance to inclement weather conditions. Many people assume that metal roofs cannot withstand high winds; however, metal roofs are much more resilient than traditional shingles. If your home has sustained roof damage from high winds and you are considering your options for repair or replacement, think of the distinct benefits a metal roof could offer.
Many areas of the country face high winds on a regular basis. The southern and southeastern U.S. often faces strong winds from tropical storms and hurricanes over the Atlantic. The Great Plains and Midwestern states often contend with tornados. High winds can cause tremendous property damage, and metal roofs generally hold up much better compared to traditional shingled roofs.
How Can High Wind Damage a Roof?
Most Tennessee homeowners know that heavy precipitation, hail, and storm conditions can damage a standard roof by dislodging shingles and allowing water to seep inside the roof. Many Nashville homeowners assume that since metal is obviously stronger and more durable than asphalt shingles, logically a metal roof should offer better protection from wind. This is generally true, but metal roofs generally have metal panels larger than average roof shingles. These larger panels may be more durable, but the roofing contractor who installs the metal roof must ensure solid connections between panels.
High winds can potentially dislodge a metal roof panel due to poor construction or ineffective installation. This can create a potentially dangerous chain reaction as most metal roofing panels fit inside one another to completely cover a roof with no gaps. However, once one panel dislodges, it can rip out adjacent panels. Installation is crucial when it comes to a metal roof. A properly installed metal roof can withstand much more punishment than a standard asphalt shingle roof or tiled roof, but poor installation can still lead to significant damage.
How Do Metal Roofs Withstand High Winds?
The two most important factors in determining a metal roof’s resistance to high winds are the material of the roof and the maximum wind speed the roof can withstand. Hurricane winds can exceed 100 miles per hour in some cases, and some metal roofs may only withstand a fraction of this wind speed. Roofers generally perform careful tests on metal roofing panels using inflatable bags to test the uplift force resistance of the roof. After laying metal roofing panels on a testing deck over plastic bags, inflating the bags beneath the roof panels simulates the uplifting force high winds can cause. Testing usually involves multiple rounds to assess the full range of resistance of the metal roof.
The goal of these tests is to ensure the metal roofing material can bend and flex with the force of wind without dislodging or snapping. Once pressure releases the roofing panels should naturally return to their original state with no signs of damage or distortion. Some experts believe that metal roofs hold up better in real-life conditions than they do in testing as pressurized air can permeate other materials near the roof panels and reduce the overall uplifting force acting against the panels from below.
Different types of metal panels in different configurations have varying levels of wind resistance. Some metal roofs can withstand extremely high winds for extended times while others may sustain significant damage from moderate to high wind speeds.
The Importance of Sealants and Fasteners
While an interlocked metal roof could potentially experience a chain reaction of dislodged interconnected panels, metal roofs held together with sealants also face unique challenges. Determine how failure-prone your metal roof sealants are by referring to the manufacturer’s information. The manufacturer should include clear designations for how strong your metal roof sealants are, including how much wind force they can withstand before sustaining damage.
If your metal roof does not use sealants, it may have mechanical locking mechanisms or feature interlocking panels held together by nothing but weight alone. This offers much less wind resistance than a sealed or mechanically fastened metal roof, so this would not be a preferable option in a climate that frequently sees strong storms with high winds.
Home and Roof Construction
The physical construction of the home and the arrangement of roof surfaces also influences wind resistance. If the home itself moves a great deal during high winds, this can easily cause metal roof panels to warp or even dislodge. Homeowners should carefully inspect their metal roofs after storms. Even minimal damage to a metal roof’s connections, sealants, and/or fasteners can eventually cause the roof to fail, leading to significant repair and replacement costs.
The construction of the home’s attic can also influence wind resistance. For example, if the attic in a home has a great deal of air intake but poor air ventilation, the pressure buildup inside the attic can cause a roof to fail in a storm. Construction and material choice are two of the most important factors when it comes to designing a metal roof.
Tennessee homeowner’s and the roofing contractor must ensure they find the right kind of material with the right fastening system to stand up to the weather conditions in the area. Additionally, they must account for the construction of the house and take air ventilation concerns into consideration. Installation is crucial to preventing high wind damage to any roof, but especially metal roofs.
Unavoidable Risks From High Winds
No matter how much time, preparation, and investment you put into your Nashville metal roof to protect it from high winds and other elements, eventually a homeowner may encounter an unpredictable problem from high wind. This may include debris flying from high winds that damages a roof, sudden changes in direction of blowing winds, and damage from falling trees and branches.
Homeowners should take care to prevent any low-hanging tree branches from damaging their metal roofs by trimming back any branches that hang over the house. During a storm these branches could easily break from the tree and fall onto the metal roof, causing severe damage. Metal roof manufacturers may not honor a warranty for a homeowner who did not adequately address unique issues on the property or who failed to trim away tree branches as required by a warranty contract.
Take time to fully consider all the climate-related aspects of your area before deciding on a metal roof and take your home’s construction and exact location into account when deciding on metal roofing materials. If high winds concern you, investing in a high-quality metal roof and hiring an experienced roofing contractor to handle your metal roof installation are some of the best methods for preventing wind damage to your metal roof instead of paying to fix it.