Up, Up and Away

The benefits of metal roofs include sustainability, compatibility with cool coatings, fire safety, low weight, recycled content, color and style options, as well as the fact that they are 100 percent recyclable. As those in the industry work to educate and inform contractors, architects, specifiers and others about the benefits of metal roofing, they are finding that the more property owners understand all the benefits of metal roofing, the more often they decide to use it.

“One of the things we often find on warranty registrations is that building owners purchased a metal roof based on its beauty and durability, and nothing else. They often are not aware of the many other benefits that come with the investment they just made,” says Todd Miller, president of Classic Metal Roofing Systems, a Piqua, Ohio-based metal-roofing manufacturer. “They are getting all of the benefits of metal roofing but it seems almost like they were never told about them.”

The durability of metal roofing offers a relative freedom from maintenance costs and worries. Although it always is a good idea to perform semi-annual inspections of metal roof systems to ensure that no unusual damage has occurred, metal roofs do not require the kind of re-coating, re-flashing and additional maintenance work often required by other roofing systems.

Although metal roofs require less maintenance than many other roofing mediums, no roof is completely maintenance free. Building owners still must be aware of some considerations. For instance, homeowners should avoid letting different types of metal touch or overlap. When certain kinds of metal come into contact with each other, it can cause an adverse chemical reaction and corrosion is much more likely to occur. For example, copper and aluminum do not behave well together. Copper and galvanized steel and copper and galvalume steel also don’t interact well. Whether it’s some kind of decoration, ornament or antenna, it is important to keep these “extras” from rubbing up against or otherwise touching or scratching a metal roof.

In the rare event that a metal roof develops a hole or open seams, a property owner should get a repair made as quickly as possible. The longer these types of defects are left unattended, the bigger the problem can become. If a roofing repair is needed, property owners should call a professional roofing contractor.

Finally, property owners and contractors should be careful with hardware. If screws, bolts or washers need to be replaced, the replacement always should be made out of the same kind of metal as the roof. Be careful to always install screws and washers only in raised parts of the roof; doing it in low parts of the roof can lead to pools of water, which eventually can cause serious damage. If you see pools of water, contact a roofing specialist right away to have it addressed.

Metal roofing also can increase a building’s energy efficiency. Many of today’s metal roof systems feature cool coatings. These coatings utilize special pigments that, even in dark colors, reflect radiant heat to keep buildings naturally cooler in hot weather. Integrated into traditional high-performance PVDF II paint systems, cool coatings can offer the best in terms of fade and chalk resistance. For buildings with low-slope roofs or other situations where a white roof is acceptable, solar reflection can be enhanced even above the level of pigmented cool coatings by choosing white or another light color where solar reflection ratings can be 60 percent and even more.

Some light-colored membrane roofs or roof coatings quickly pick up dirt and biological growth, thus reducing solar reflectivity. One of the benefits of Kynar coatings is the resistance to biological growth and dirt; however, if a metal roof is in a very dirty area, such as an area prone to tree sap, occasional cleaning with clear water can help maintain the roof’s reflectivity.

With many metal roof systems, additional energy efficiency can be achieved through ventilation beneath the roof panels. Called above sheathing ventilation, this sort of application combines eave vents for intake and a ridge vent for exhaust. This combination, when located directly beneath the metal roof, will carry away the sun’s heat before it gets inside the structure. In many cases, energy savings can be as high as 30 percent when these types of systems are installed. Above sheathing ventilation cannot be installed to an existing roof, but is highly recommended when re-roofing.

One of the latest innovations in standing seam metal roofing is the incorporation of integrated solar collection systems. Rather than making penetrations in the roof to mount traditional photovoltaic panels, these integrated systems are part of the roof system itself. With proper sizing and design, an integrated solar system can meet a large portion of a building’s electrical needs. This allows property owners to pay for roofing and simultaneously achieve ongoing reductions in their utility costs through an integrated roof and power system.

The only maintenance consideration for solar panels is to check the panels periodically and remove any debris or dirt. Bird droppings, sap, pollen and grime all can accumulate on panels and will severely reduce the panel’s energy-producing capacity. Warm water and dishwashing soap are all that are needed to maintain solar panels.

Property owners who choose metal roofing may indeed appreciate its beauty and durability, but the benefits go far beyond that. As contractors and design professionals come to really appreciate and understand the full benefits of metal roofing, more and more of them will choose from the wide offerings of metal products that are available.

Bill Hippard is president of the Belfair, Wash.-based Metal Roofing Alliance. He also is vice president of sales for Precoat Metals, St. Louis. He can be reached at Bill_Hippard@Precoat.com.