San Antonio, TX - Traditional building construction methods of sun protection, began with thatched roofs, and progressed to materials that included wood, steel, PVC, fiber glass, canvas and more recently industrial fabrics that include shade netting. Shade netting is used in the form of shade structures and are becoming a more familiar sight in the landscape of America. Shade structures were first introduced to the United States in the mid 1990's, and now in their second decadal presence are proving their strength and durability as market acceptance continues to grow and take root. Trico-USA Inc., one of the leading shade structure manufacturers, have designed various forms and shapes of TricoShade structures using UV stabilized polyethylene for a wide number of target markets.
In this article we will examine a few of the differences between canvas, polyethylene and PVC, and what makes these materials like chalk and cheese, and how they behave in the elements.
Some of the differences between polyethylene and canvas is in its chemical composition. Canvas being a natural fiber performs differently, in that being natural it attracts bacteria and is therefore more prone to mold, mildew, rot and fading. Polyethylene on the other hand is synthetic and is manufactured from high density UV stabilized polyethylene; the UV additives are included in the extrusion process at the manufacture of the shade netting which further adds to its durability. Polyethylene does not absorb moisture which further enhances its resistance to wear.
And what of its design capabilities? Unlike canvas, polyethylene has high resiliency and excellent elastic properties, and through a process called 'stentoring' it is set against unraveling and allows the fabric to retain its original tautness. The weight advantage, i.e. low specific gravity, gives architects an extra design appeal due to the weight advantage, making it lighter for the steel structure while being superior in strength to other heavier fabrics.
And what of the nature of PVC? While this may be favored on projects that require waterproofing, it poses design challenges in that it has high weight considerations being 2-4 times the weight of shade netting, which affect the engineering process. This means that due to the weight of the PVC the steel structure would require heavier steel thus increasing the price of the structure.
SOURCE: TricoShade structures