When selecting the fasteners for your metal roofing system, you'll have two options: concealed or exposed. As one would expect, the former is hidden from view while the latter is visible in plain sight. There are pros and cons to each, and its important to always match the proper fastener-type with the right metal roofing system.
Concealed fastener metal roofs provide a clean and streamlined finish. While a bit more expensive and labor intensive at the outset, they deliver multiple benefits, including:
- Reduced wear and tear on the fasteners
- Less distortion of the roof panels
- Increased leak resistance
- Improved looks
Spend time browsing websites and brochures from metal building manufacturers to pick a few styles you like, then work more closely with a preferred manufacturer to make sure the roof and fastener systems work with your climate and your building codes.
Benefits of Concealed Fastener Metal Roofing
The following are expanded benefits of using concealed fasteners for your roof.
- Reduced wear and tear. The more exposed a building component is to the outdoors, the more wear and tear it will withstand via water, wind, debris, UV rays and other environmental factors. Since concealed fasteners are hidden below the metal sheeting, they are exposed to far fewer elements and are less prone to corrosion. As with all metal building components, purchasing high-quality materials - with the right protective coating for your building's climate, location and exposure - will make all the difference in its projected lifetime. The stronger your fasteners are, the greater the roof's structural integrity will be.
- Less distortion of the roof panels. Metal building panels, like all solid structures, respond to changes in temperature. In the case of roof panels, you'll notice a slight expansion and contraction in response to heat and cold, respectively. When the panels are fastened from the top, which is the case with exposed fasteners, this movement is more visible and is referred to as distortion. If the distortion is too severe over time, panels may even need to be replaced because - in addition to being unsightly - permanent distortion can cause damage to attached and surrounding structural elements. Roof distortion is minimized using concealed fasteners, which do not pin the panels down from the top, allowing them more room to expand and contract.
- Increased leak resistance. Water and moisture are the enemy to almost any building. Wherever they are present, you are bound to find mold, mildew, rust, corrosion and/or structural rot, leading to costly and labor intensive repairs and replacements. The more water-tight your building is, the better. Concealed fasteners increase leak resistance because they are hidden underneath roof panels, rather than fastening through them. Even the most conscientiously installed exposed fasteners leave tiny gaps between the fasteners and the panels. Over time, water is bound to infiltrate the gaps and this can eventually lead to slow leaks that ultimately contribute to unnecessary structural damage. With concealed fasteners, the structural integrity of the panels will ultimately determine weather-fastness - not the fasteners or penetrations.
- Improved aesthetics. Of course, this point is entirely objective. As many modernists know, corrugated roofs - using exposed fasteners - are just as likely to provide the aesthetic a building owner desires. However, in most cases, those who prefer a more streamlined and traditional roof line appreciate the clean lines provided using concealed fasteners. And, even those those enjoy the wavy look of corrugated metal roof panels can appreciate the unfettered lines (or waves) created by concealed fasteners. For many, they're simply a more stylish and high-end look.
Enhancing the Performance of Concealed Roof Fasteners
The integrity of your roof goes beyond the fasteners however, and becomes part of a more integrated system consisting of things like quality, coating, insulation and accessories. The following are some steps for enhancing the performance of a metal roof with concealed fasteners.
Quality materials and craftsmanship. It's easy to gravitate towards the lowest bid but don't make the mistake of sacrificing quality for thriftiness. A few extra dollars spent on high-quality fasteners and roofing panels from a reputable building supplier, and installed by an experienced metal roofing contractor, will increase your roof's low-maintenance and durable attributes.
Select the proper coating. Number 3 above stated that the integrity of the roofing panels ultimately determines a roof's weather-fastness when paired with concealed metal roof fasteners. To enhance your roof's integrity, select a coating that makes sense for your climate. Buildings exposed to salt air or environmental toxins require more heavy-duty coatings than those that don't. Cool metal roofs are recommended for buildings in warmer climates, slowing down the effects of UV exposure - not to mention the benefits associated with interior comfort and energy efficiency.
Opt for the bells and whistles. Pay careful attention to the "entire package" when choosing a metal roofing system. Often, things like gutters and downspouts - although essential to directing water down and away from the building - are not included. Adding them to your package, however, is typically more affordable than buying them aftermarket. Also, look for qualities like water-shedding or waterproofing roofs, which both work in different ways to reduce a metal roof's water exposure.
Don't neglect a radiant barrier and insulation. Finishing the installation of a metal roof is a large part of the equation but there is another step that is integral to the roof's performance and that is the radiant barrier and insulation you use. Not only do these essential items improve your home's interior comfort and energy efficiency by blocking solar heat gain, they are also integral to preventing condensation that leads to long-term moisture damage.
Using concealed fasteners - along with the additional elements of a durable, weather-tight metal roof system - will guarantee an efficient and functional roof for many decades to come.