Over the years, canvas tarps have fallen by the wayside in favor of vinyl tarps. Vinyl tarps are lightweight, stain-resistant, heard wearing and resistant to moisture. The weight is one of the primary factors in making them the tarp of choice.
These vinyl tarps are seen everywhere, they are used as drop cloths for painting as well as covers for boats, patio furniture, BBQs and swimming pools. Depending on the size, the tarps are fitted with grommets with are made from aluminum or other corrosion resistant material. The grommets make it easy to tie the tarp down with rope or bungee cords. The most common color for vinyl tarps is bright blue, but they can be had in many different colors, other favorites are green, black and silver. Green is usually the choice when the tarp is used to cover a sports field, silver is ideal for reflecting the sun’s rays. The tarps are made in different grades of vinyl for different purposes; some are treated for UV protection which greatly extends the life of the tarp when it is permanently installed outdoors.
Tarps are usually classified by material, material thickness and grommet strength. When tarps are ordered, regardless of the material, they are about five percent smaller; this is to compensate for the doubling over the material around the tarp perimeter. The grommet strength is a combination of the material, aluminum vs. stainless steel for example and the grommet spacing. Tarps which need to withstand severe wind will often have grommets at 18” spacing, other tarps used for simple domestic purposes may have the grommets spaced as much as five feet.
Common material is polypropylene, canvas and vinyl tarps.
Polypropylene: Tarps made of this material are a laminate of sheet material and woven material. The center is loosely woven polypropylene sandwiched between two sheets of the same material. This method of manufacture makes the finished material resistant to stretching in all directions including the bias and makes it waterproof. Most polypropylene tarps are treated for protection from UV light, those which are not do not last near as long; they become brittle; lose their strength and their water resistance.
Canvas: Canvas, the forerunner of all modern materials, is not waterproof but it is water resistant. If the canvas tarp is left saturated with standing water for very long, the water will leak through the material. Canvas tarps are very heavy; they are often treated with fire resistant chemicals and then used as welding covers to stop the surroundings from getting burnt with hot welding sparks or slag.
Vinyl: Vinyl tarps are considered the super-duty industrial grade tarp. They are 100% waterproof and abrasion resistant. The resists almost all greases and oils and are mold resistant. Vinyl tarps have high resistance to tearing and are often used as truck covers.