Reasons Why Metal Roof Repair Fails
We Can Solve Your Metal Roof Issues
Mistakes made when designing and installing new metal roofs can cause major problems. The areas where common problems tend to not occur in selecting the system. Most of the problems that metal roof repair leaks are caused relate to the various details that are used for finishing metal roof systems. Those mistakes are not immediately obvious after the installation is completed. It can take time for them to develop.
The following are five of the most common problems that are found when a metal roof’s condition is being assessed.
Horizontal Seam Openings
It is hard and impossible at times to produce metal roof panels that are able to extend a building’s full rafter length. The project designer in some designs limits how long the panels can be based on contraction and expansion.
Due to the panel length restriction, horizontal seams must be installed onto the roof system by the installer. The horizontal seams are perpendicular to the metal roof’s standing seams.
Over time, horizontal seams can separate. In a hydrostatic metal roof system, an opening can be created that allows water to get back into a building.
Penetration Flashing Openings
Metal roof systems are susceptible to contraction and expansion. This is due to metal panels moving as temperatures change. Stress at attachment points occurs due to this movement, in addition to penetration throughout the roof system. This stress results in the flashings breaking down at the penetrations, resulting in leaks in the roof.
A metal roof system is built by individual metal panels being attached together at the point of the seam. After installing metal roof systems, it is hard to remove or disassemble them.
In contrast to asphalt shingle systems, metal roofing systems cannot be disassembled to repair the penetration flashing. That makes it harder to do long-term repairs, especially when the penetration was installed following the metal roof installation.
Commercial Metal Roof Repair Companies With the Experience You Need
Oxidation of Metal Roofs
A broad range of materials is used to make metal roofs. They include zinc, copper, tin, aluminum, and steel. Some of those materials are prone to oxidation. Sheet metal that has a protective surface coating is used to make a majority of metal roof panels. This coating over time can end up wearing away which results in the metal panels oxidizing.
A number of problems can be caused by surface oxidations. Those problems may include structural failure with structural system metal roofing systems. Repairs are also impeded by oxidation. Metal panel oxidation that occurs at exposed fastener heads which makes it hard to apply sealant.
Fasteners Backing Out
Typically, metal oof systems are comprised of a combination of concealed and exposed fasteners. The fasteners may be screws or nails. Typically, exposed fasteners come with a neoprene washer which seals the head of the fastener to the metal roof panel’s surface.
Fasteners over time tend to back out from their seated position. There are various reasons why this may occur. Fasteners may back out due to wind uplift. Under wind conditions, metal panels may vibrate which can lead to the fasteners backing. Another thing that can cause fasteners to back out is freeze-thaw. When the neoprene washer is dried out, it allows water to get in. During the winter, water may freeze and expand which can result in fasteners backing out.
Headwall/ Open Ridge Flashing
Roof systems can terminate into other types of conditions on a building’s surface. Those conditions can include wall details rising when the roofing matches with other surfaces. One example is a metal roof system that ends in a rising wall under a signed band at a shopping center.
This area tends to develop weaknesses. It is often due to poor details in the original installation. Those details need closure strips so that water is prevented from blowing back onto the detail. Sometimes this closure strip is not installed by contractors. The underlayment initially waterproofs a roofing system against blowback. Moisture may penetrate the roof system as the underlayment continues to age.
Metal roof leaks can be caused by other sources. The five above are the most common sources to initially check. Knowing where you should look for possible leaks is just half of the battle.
Armadillo Roofing & Exteriors (512) 333-7663 provides commercial metal roof coating, commercial metal roof restoration, commercial metal roof repair and commercial metal roof installation services to Austin, Texas and the surrounding Austin area communities. When you need good, experienced advice regarding your commercial metal roof, give us a call.
You can also visit our sister site, TaurusEliteRoofing.com, if you need additional help with commercial metal roof restoration or repair.