Most of the inexpensive modern tarps we see today are made from woven polyethylene; this material is used so widely that many refer to it as poly tarp.
Some tarps are still made of canvas or vinyl and are used mostly for specialized applications. Formerly, canvas and canvas-type tarps were heavy and bulky. To make them waterproof, they were treated with tar or paint. They also had a tendency to pick up moisture, and as one might expect, they had low to no flexibility in freezing temperatures. They would become even more bulky and cumbersome with age because canvas is a natural fiber material and prone to moisture retention, mildew and decomposition.
In the early sixties, fabric tarps were coated with nylon, polyester or polyethylene. This was a great advancement in tarp design. Polymers were just starting to take hold in industrial and consumer markets. Polymers made products much more versatile and durable, as well as spawning a plethora of new lightweight and inexpensive items. For tarp design and construction, woven polyethylene eventually became the dominant material.
Advances in polymer science and engineering have influenced great technical strides in the last decade. As a result, most of the tarps used today are made of reinforced woven polyethylene. The best available technologically advanced tarps are composed of a three-layer, laminated, high-density polymer woven for multidirectional strength. They feature heavy-duty aluminum grommets on the corners and around the tarp’s hem, which are spaced thirty-six inches apart.
These coverings have extra-heavy polyester roping sewn into the hems, allowing one to securely tie down the tarp. As the base material of polyethylene has remarkable properties, they naturally possess cold temperature flexibility and are crack resistance down to minus 20 degrees Fahrenheit. They are water, mold, mildew and rot resistant in the harshest and wettest of environments and even when in direct contact with the ground. They are tear, acid and ultra-violet ray resistant. Many of the higher quality tarps are silver in color, permitting the sun’s rays to be reflected. This keeps the covered item much cooler than it would be if it were protected with a dark or transparent outer surface.
Modern tarps come in a variety of thicknesses, densities, colors, shapes and sizes. Unlike the old canvas, polyester or nylon designs, woven polyethylene tarps are an incomparable consumer value. The practical uses for quality modern tarps are virtually endless, with the durability and versatility of tarp construction born from modern polymer science.