- Resealing open seams
- Reflashing all roof penetrations
- Metal roof oxidation repair
- Metal roof maintenance
- Installation of standing seam and corrugated panels
Some common metal roof issues:
- Open seams
- Open penetration flashing
- Metal roof oxidation
- Fastener backout
- Open ridge/headwall flashing
- Loose counterflashing
- Improper installation methods
- Panel damage
Metal roof systems are prone to expansion and contraction. This is a result of the metal panels moving because of temperature changes. This movement creates stress at points of attachment as well as at the penetrations through the roof system. The stress leads to the breakdown of the flashings at the penetrations which result in roof leaks.
Metal Roof Oxidation
Metal roofs are made from a wide variety of materials. These include steel, aluminum, tin, copper, and zinc. Some of these materials are subject to oxidation. Most metal roof panels are made from sheet metal that has been coated with a protective surface. Over time this coating can wear away leaving the metal panels to oxidize.
Surface oxidation can lead to problems. These problems can include structural failure if the metal roof system is a structural system. Oxidation also impedes repairs. Metal panel oxidation at exposed fastener heads can make sealant application difficult.
Fasteners Backing Out
Metal roof systems typically include a combination of exposed and concealed fasteners. These fasteners can be nails or screws. Exposed fasteners typically have a neoprene washer that seals the fastener head to the surface of the metal roof panel.
Overtime fasteners have a tendency to back out of their seated position. This can be for various reasons. Wind uplift can lead to fastener back out. Metal panels will vibrate under wind conditions leading the fasteners to back out. Freeze-thaw can also lead to fastener back out. As the neoprene washer dries out water can enter in. In winter time conditions the water can freeze and expand leading to the fastener back-out.
Metal roofing is a popular option for new roofs, especially due to its reputation for longevity and attractive curb appeal. Metal roofing can last far longer than asphalt shingles.
Metal roofing provides many advantages, including the ability to withstand nearly any type of weather condition while keeping the home cozy and dry. Rain easily drains quickly from a metal roof, and snow can melt and slide off a roof very efficiently as well. Metal roofing can be obtained in various levels of quality, including roofing with fire resistance and the ability to withstand a hail storm without damage. Metal roofing comes in many different colors and finishes including the look of natural cedar shakes or stone. It is a very attractive roofing option for many business owners. It can be expensive, but the durability and longevity it provides easily justify the additional cost.
Open Ridge/Headwall Flashing
Roof systems need to terminate into other conditions on the surface of the building. These conditions include rising wall details where the roof system matches into other surfaces. An example of this would be a metal roof system ending into a rising wall, This is an area where weakness typically develops. In many cases, it is because of poor detail from the original installation. These details require closure strips to prevent water from blowing back into the detail. Contractors may forgo the installation of this closure strip. Initially, the underlayment waterproofs the roof system against the blow-back. As the underlayment ages, moisture can penetrate into the roof system.
Standing Seam Roof example below
Ribbed/Corrugated paneled Roof example below
The reason for installing a standing seam metal roof – whether for commercial or residential applications – is probably aesthetics. Properly installed, a standing seam roof will not only provide decades of service but will provide a distinctive, elegant look to virtually any home or building design. Color is, of course, critical in this respect, but also important is how edges and other details are “finished” to complete the roof.
Standing seam panels can be bent effectively to terminate securely and cleanly at the drip edge of the roof and other locations, virtually eliminating the potential for wind uplift damage. In addition, metal trim components (rakes, caps, and other flashing pieces) are custom-made for each roof, ensuring good aesthetics and an excellent, long-term, watertight and bird-proof fit through all weather conditions.
In contrast, roofs with panels made from ribbed metal are usually not trimmed or finished effectively, because the ribs/striations in the panel inhibit bending the metal to provide a clean termination at the roof’s gutter edge and other areas.
Foam is often used to close gaps on ribbed panels, which can deteriorate over time, inviting wind uplift problems.
Trim details for corrugated metal roofs are typically one-size-fits-all items that have to be adjusted to install properly. This can lead to problems down the road when the roof is subject to expansion and contraction, and components can work themselves apart, inviting water penetration and bird nesting.