In general, a tarp is a large sheet of material that is flexible, water resistant or waterproof, and can be used for a wide range of protective purposes. The material they are made of, however, can vary widely: cotton, polyester, polyethylene, polypropylene, polyvinyl chloride, or others. The sheet could even be an open mesh made from any number of those materials. Canvas tarps are typically made from cotton, polyester, or a combination of the two. The fabric-based tarps are the traditional type of tarp, and they are still quite commonly used.
The most common use of tarps is to cover and protect valuable materials from the harsh effects of weather, as well as the hazards inherent in transportation. Why are canvas tarps a good option, perhaps even the ideal option in some situations?
Many canvas tarps are made of high quality cotton duck fabric, making them a good ecological choice.
Cotton is a renewable resource, unlike the oil used to make the petrochemicals that many other tarps are made from.
If you maintain a cotton canvas tarp properly, it can last for a number of years, reducing waste.
When cotton canvas tarps begin to age, requiring disposal and replacement, the aging tarp will be biodegradable, causing little to no harm to the environment. This is in stark contrast to poly tarps, which only break into small pieces that do not decompose. They will either end up in a landfill or in tiny plastic pieces polluting the environment. With cotton canvas, you prevent those issues.
Canvas tarps, regardless of the fabric type, allow airflow between their fibers. This does not affect the water resistant treatment on the tarp, but allows air to circulate beneath and through the tarp. This breathability helps to prevent atmospheric moisture from building up beneath a tarp and condensing, which would get anything beneath wet. If the tarp is meant to keep something dry, this seems incredibly ideal. For this reason, canvas tarps are highly recommended for covering moisture-sensitive items.
Canvas tarps are relatively lightweight, and they also have strong slip-resistant properties, making this an ideal choice if you must have a tarp somewhere that people will be walking over it, but especially if it's wet and cold.
Most canvas tarps available on the market are treated for water resistance. The manufacturer applies either an oil-based product or a wax-based product to achieve this effect. It's important to note that water resistance is not the same as waterproof. As long as a tarp is kept taut and angled, moisture will bead up on its surface and roll right off. However, if water is allowed to pool on the surface, it will begin to seep through. This is easy to avoid by setting up your tarp properly.
Canvas tarps are used in transportation, farming, warehousing, and industrial spaces. Some canvas is even manufactured to be flame resistant! There are dozens if not hundreds of uses for these utilitarian products.