C+S February 2021 Vol. 7 Issue 2 (web)

Of course, fieldhouses and practice facilities for sports like football and soccer typically do require a lot of space, another area where rigid- frame fabric buildings prove cost-effective. The inherent strength of these I-beam structures, combined with lightweight fabric cladding, allows for long clear span roofs with no support beams. Old-school fabric structures lack the true engineering integrity neces- sary for really long spans. Brick-and-mortar buildings are structurally sound, but the larger the building needs to be, the greater the price difference between traditional construction and rigid-frame fabric buildings, which can be installed at a fraction of the cost. Interior Environment Another construction option that has long been popular, due to its price tag, is steel buildings. While steel-sheeted structures can help fill a certain niche in the industry, their cost-saving advantage gradually disappears as the building dimensions become larger. And no matter what size structure is required, steel buildings tend to fail the aesthetics test, generally offering poor lighting and acoustics. By contrast, the interior environment inside a fabric building offers a softer feel, better acoustics with less echo, and much improved lighting due to the reflective properties of the fabric material. People who’ve never set foot inside a fabric sports structure often comment that the atmosphere exceeds their expectations. While having an attractive venue is certainly beneficial to those using or visiting the building, engineers and architects will also take notice that the same materials used to create that welcoming atmosphere are actually serving another purpose in helping to meet building codes. For projects where state or local energy codes must be met, a rigid-frame design allows building suppliers to easily apply insulation – typically with R values ranging from R-19 to R-30 – along the interior of the structure. The insulation is secured and then covered with a fabric liner that is actually the same type of fabric used for the exterior cladding. Polyvinyl chloride (PVC) has the been the primary fabric of choice for

sports facilities for many years because of its durability. The fact that users can select different colors of fabric to match their team, school or organizational branding is also a selling point for fabric in general. Leg- acy Building Solutions offers a newer fabric called ExxoTec™ PVC that delivers more durability and a longer life expectancy, due to the added layers of primer and lacquer around its high-strength woven fabric. To install the fabric, Legacy relies on its patented fabric attachment system that uses half-inch diameter bolts to clamp a keder rail to the top flange of the structural steel frame. Fabric panels are then slid through the keder channel to connect to each beam. This process allows fabric panels to be pulled into place with the properly calculated horizontal and vertical tensions. Wider fabric panels are used for the interior than the exterior of the building, but otherwise the process is the same both outside and inside. With the interior liner tightly secured, maintenance concerns for the fabric cladding itself are practically nonexistent. Behind the Scenes For many industries, the I-beams in a fabric building are left exposed and may require some kind of treatment to protect the steel. Since the structural frames in most fabric-cladded sports facilities are encap- sulated by insulation and liners, typically a primer coating is all that needed to treat the beams. That said, building users in coastal locations or who experience high humidity conditions due to their facility application – such as a swim- ming pool – could consider epoxy paint for I-beam treatment to protect against corrosion. Because the steel beams are permanently out of view, some users might choose this option purely for the peace of mind of knowing that the structural frame is well protected. It is worth noting that the rigid frame building design allows for ef- fective passive ventilation within the walls. Ridge and soffit vents use the natural movement of warm airs to help remove moisture from the insulation cavity, another key piece in meeting building codes for a given environment.

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FEBRUARY 2021

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