Both tensile fabric buildings and tension fabric buildings continue to gain popularity because they are typically more affordable, easier to install, and span large distances without interior poles or pillars. However, the difference between the two is not always clear.
In practice, tensioned fabric structures tend to carry both tension and compression. However, it is the degree to which a structure is intended to stabilize that determines whether it is considered a tensile fabric building or a tension fabric building.
Tensile fabric structures are constructed using PTFE-coated fiberglass, ETFE film, or PVC-coated polyester as the membrane materials, along with mild steel cables, stainless steel, or aramid fibers for the structural frame. Tensile fabric structures are commonly known as thin-shell structures that create a dramatic piece of architecture due to their double-curved shape, which provides most of the structure’s strength. By forcing the fabric to take on a double curvature, the fabric gains sufficient stiffness to withstand the loads it is subjected to. In tensile fabric structures, the fabric does not crease thanks to the tension in the membrane.
Tensile fabric structures are often used for lightweight or temporary installations. The lighter weight makes these structures easier to transport, and the flexible materials can create an impressive feature. There are a variety of uses for tensile fabric structures, including:
Tension fabric structures are constructed with steel frames and industrial-strength fabric membranes where the fabric membrane is tensioned. In a tension fabric building, the steel framework provides all the structural support rather than the fabric membrane. For example, as a load is imposed on the top chord of the truss of a tension fabric building, the top chord will be in compression and the bottom chord will be in tension. Fabric tension buildings are constructed in modules using overhead cranes and held in position by tension forces imposed by the structural framework or cabling system.
Tension fabric structures are frequently used to create more permanent storage buildings or indoor recreational facilities. Tension fabric structures can reduce a building’s energy consumption and block UV rays that induce heat. Common uses for tension fabric structures include:
Tensile fabric structures typically use less material than tension fabric structures which results in a much lighter structure. While they can be used to create entire buildings, tensile structures are more common for intricate design work or landscaping features. Tensile fabric structures carry only tension rather than compression. For example, tensile structures are essentially a piece of fabric pulled in opposite directions. The sufficient stiffness that the fabric gains from the double curvature is what withstands the loads that the building is subjected to.
Tension fabric structures tend to be stronger and more durable than tensile fabric structures. These structures are typically engineered and fabricated to meet structural, flame-retardant, weather-resistant, and natural force requirements so that they meet strict building codes. The steel framework provides all the structural support in a tension fabric building; the fabric acts as the protective cover, letting in natural light while keeping the elements out.
Tensile fabric structures have various features that make them ideal for short-term use. These options use less material than tension fabric structures because the fabric is often thinner and they use cables rather than a strong steel framework for stabilization. Since these structures use less material, they are much easier to transport to new locations and store when not in use.
Tension fabric structures are more suitable for long-term use. These optios use a sturdy steel frame to hold the fabric in place and give it shape. This steel frame can endure generations of use, making it an ideal building option. Tension fabric structures also use a more durable fabric material that can hold up to the elements even when used constantly for many years.
Tensile and tension fabric buildings have similar installation processes, though the equipment used may vary depending on the structure’s size. Tensile buildings are often smaller, so they require less heavy machinery during installation. In either case, installers often use lift equipment like forklifts, hydraulic jacks, or cranes to construct the metal frame, stretch the fabric covering over the top, and attach any additional hardware.
Though the specific equipment and installation process may vary for tensile and tension fabric buildings, installation for these structures is often much faster than typical wood, metal, or brick construction. The durable frames and materials also allow fabric structures to stand the test of time, just like a traditional building.
If your project requires an engineered, built-to-last fabric structure, then a tension fabric structure is your answer. Calhoun’s tension fabric buildings are engineered site-specific using our unique 3D Nonlinear Finite Element Analysis. We model the true behavior of fabric relative to environmental factors producing the most suitable fabric structures to meet your requirements, and the longest-standing structure in the industry. We also use engineered high-density polyethylene (HDPE) fabric manufactured from 12 oz per square yard in weight, and 24 mil thick. Known for its large strength-to-density ratio (which can range from 930 to 970 kg/m3), HDPE provides stronger intermolecular forces and strength than other tension fabric membranes.
