When a job requires the use of heavy-duty tarps of a very specific size, it is important to understand how they are sized. Having one that is too small can expose stored materials and equipment to the elements and can lead to damage or loss. Oversized covers can present a problem if excess material gets caught or pinched. For a truck tarp, if the excess material is left loose and flapping, this can also expose the materials underneath to the elements.
To better understand how to buy the right size banner for a specific job, it’s important to know the difference between cut size and finished size, how size can change with use, and what materials are best suited for certain jobs.
How are they classified and sold?
Heavy duty tarps have two specifications when it comes to size. First of all, the cut size is the size of the fabric when it is first cut, but before it is folded and manufactured into a finished product. The finished size, then, is the actual size of the finished product after folding and sewing the hems of the fabric and sewing the seams. The finished size will always be smaller than the cut size. These two terms are important when requesting custom solutions. When placing an order it is vital to ensure that the product will be the correct size after it has been manufactured and delivered.
Can they change size?
Some materials are known to change size. For example, canvas tarps are susceptible to shrinking over time. Since they are made from natural fiber, they tend to shrink as they get wet and dry in cycles. It is difficult to predict precisely how much the size will vary, but a safe estimate would be 6 inches or 5% of the longest dimension, whichever is greater. For specific work applications where exact sizing is especially important, canvas is often not a good choice.
Materials that do not change in size are known as size stable; this is another important term to know when ordering a custom product.
Materials selection
Since banners can vary in size during use, it’s important to choose the right material and not just the cheapest option. As mentioned above, canvas is not a stable size and should be avoided if shrinkage is an issue.
Fortunately, there are many options for stable size materials. Polyester, vinyl, neoprene and blue tarps are stable options in all sizes. Blue polys tend to be a popular choice due to their low cost, light weight, and flexibility in a wide variety of uses. Vinyl is a stronger material than poly, so it is used for truck tarp products, allowing these covers to be used on trucks and trailers. Neoprene is a high-strength, high-cost material that is resistant to chemicals and works well for high-end use.
Ultimately, sizing heavy duty tarps is a simple process. Please note the difference between the cut size and the finished size. Then choose a size-stable material like polyester or vinyl, or go with canvas if variable sizing isn’t an issue.