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Are you trying to design the perfect patio for your garden?Apart from choosing an elegant paving material and deciding on a trendy shape, you’ll need to take charge of some tedious but equally important tasks . Importantly, you need to calculate the quantities of all materials, including the gravel base, that will be placed under the paving. If you underestimate the amount of gravel you need, you could end up having to make an unscheduled last-minute trip to the supply store, or worse, take shortcuts and end up laying less gravel than necessary. Conversely, overestimating your needs will leave you with a pile of wasted gravel at the end of the project. To save time and money, you want to avoid these mistakes when designing your patio.
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At first glance, calculating the amount of gravel is a very simple task that requires only basic arithmetic. To estimate the amount of gravel, multiply the length of your patio by its width, then multiply by the depth of your granular layer. Sounds easy, right? Well, there’s a little more detail to the calculation. First, you probably already know that a solid gravel foundation is a key element in ensuring pavement stability and uniformity. To give this foundation sufficient strength, the depth of the gravel layer must be established. Similarly, you need to determine the size of the gravel, which will determine its weight. Give the final figures to the material store clerk at the time of purchase. Below we provide an example of calculating the amount of gravel for a standard residential patio. It allows us to emulate the same steps in our calculations.
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Steps to calculate the amount of gravel needed
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Let’s say you plan to pave a 15-foot by 20-foot area in your backyard for a patio. It’s amazing. Two of the important variables in the formula are already known: 15 feet and 20 feet. Next, consider the depth of the gravel. Generally, you want a granular layer that is at least 4 inches deep. However, increasing the depth to 6 inches may be a wise choice to give the base a little more strength. Assuming you use a 6-inch deep layer, there are three variables needed to calculate the gravel volume: 20 feet long, 15 feet wide, and 0.5 feet deep. Multiply the length, width, and depth to get 150 cubic feet of gravel. Now, let’s convert this product to cubic yards. There are 27 cubic feet in 1 cubic yard, so dividing 150 by 27 gives you 5.56 cubic yards.
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Nowadays, gravel is usually sold by the ton, so you need to determine the weight of this material. There are many different types of gravel, but let’s say you use 3/4-inch gravel, which is pretty standard for patio base applications. Let’s say one cubic yard of 3/4-inch gravel weighs 2,565 pounds. To find the total weight in pounds, multiply the total volume (5.56 cubic yards) by 2,565 to get 14,261 pounds of gravel. Finally, divide this product by 2,000 to convert it to tons, which is 7.13 tons. That’s it. You can purchase this gravel weight by taking it to a supply store.
