How to Measure Your Space for Custom Tarps
Whether you're covering a piece of equipment, creating a shaded outdoor area, or protecting cargo on a flatbed truck, ordering a custom tarp ensures you get the exact coverage you need. But to get the best results, you must first take accurate measurements of your space or object. Improper measurements can lead to wasted material, poor coverage, and unnecessary expense. Fortunately, measuring for a custom tarp is simple if you follow a step-by-step process and know what to look for.
This guide will walk you through how to correctly measure your space or object for a custom tarp, so your investment pays off with a perfect fit every time.
1. Start with a Clear Objective
Before grabbing your tape measure, think about what you're covering and why. Are you protecting equipment from rain? Blocking sunlight on a patio? Securing items on a trailer? Understanding the purpose of the tarp helps you determine the right fit, material, and shape.
Ask yourself:
Does the tarp need to cover only the top or the sides as well?
Will it be stationary or used in a mobile application?
How tight or loose should the fit be?
Defining the tarp’s function will help you plan your measurements accurately and decide if you need features like grommets, flaps, reinforced edges, or extra overhang.
2. Measure Dimensions Accurately
Once you’ve defined your purpose, begin taking the basic measurements. Use a reliable tape measure and, if possible, have someone assist you for long distances or awkward angles.
For rectangular or square objects:
Measure Length from one end to the other.
Measure Width across the object or area.
Measure Height if you want the tarp to cover the sides.
For circular or irregular objects:
Measure the diameter or circumference for round shapes.
Take multiple measurements at different angles to account for any irregularities.
Pro tip: Always double-check your measurements and write them down immediately to avoid confusion or mistakes.
3. Account for Overhang and Draping
If you're ordering a tarp to fully enclose or protect the sides of an object, you’ll need to add extra inches or feet to your measurements. This added length—called the overhang or drape—ensures the tarp wraps around the item and provides complete coverage.
Here are common recommendations:
Add 6–12 inches on each side for a snug fit.
For tie-down applications, consider 12–24 inches of extra material for folding and fastening.
For overhead coverings (like canopies or roofs), think about wind, rain runoff, and where you want the water to drain.
Keep in mind that if you're planning to use grommets or ropes, that extra space will give you room to tie down the tarp securely without lifting it off the covered object.
4. Consider Shape and Fit Customization
Not all spaces or items are simple rectangles. If you’re working with uniquely shaped equipment, oddly sized storage units, or angled structures, you may need to sketch the shape and specify dimensions for each segment.
For irregular shapes:
Break the object down into smaller, measurable parts (e.g., top, sides, corners).
Note any curves, slopes, or angles.
Include the height and width of each section, especially if you're covering a 3D object.
If needed, create a basic diagram or outline with dimensions labeled clearly. This can be very helpful when communicating with the tarp manufacturer to avoid misinterpretation.
5. Include Features and Finishing Details
After determining the size and shape, consider the final features of your custom tarp. These finishing details not only affect function but also slightly impact the final dimensions.
Things to consider:
Grommet Placement – If you're adding grommets for tie-downs, specify how far apart they should be (e.g., every 18”, 24”, or corner-only).
Reinforced Edges – Hemming or double-stitched seams may slightly reduce the total coverage area.
Cut Size vs. Finished Size – Some manufacturers list the "cut size" (before hems and seams), which can be 3–6 inches larger than the "finished size." Always clarify which size you’re working with.
Flaps, Pockets, or Velcro – If you need special closures or features, provide exact placement and size to ensure proper fitting.
Always communicate clearly whether the size you're providing is the final size needed or whether the manufacturer should adjust for finishing and reinforcement.
Conclusion: Precision Pays Off
Custom tarps are an investment in protection, and that protection starts with accurate measurement. By understanding your tarp’s purpose, taking precise dimensions, allowing for overhang, adjusting for shape, and adding functional details, you ensure your tarp fits exactly as needed—no sagging, gapping, or wasted material.
Proper planning up front leads to long-term performance, easier installation, and greater satisfaction. Whether you're covering a small grill or a large commercial vehicle, the time you spend measuring correctly will pay off with a tarp that delivers both value and peace of mind.