How to Calculate Sod
Buying sod requires knowing exactly how much you need. Ordering too much leads to wasted money, while ordering too little becomes a headache when you have to stop the work and wait for more sod. Measuring your yard accurately is key in determining how much sod you need. Breaking your yard down into smaller sections helps you create accurate measurements.
Calculating Squares and Rectangles
Some yards fit into neat, square packages. These are relatively simple to measure. Determine the length and width of each yard section, such as front yard, backyard and side yard. Multiply the length and width of each section individually to determine square feet; for example, if your front yard is 20 feet by 20 feet, you have 400 square feet. When you have the square footage of each section, add them together for the total square footage.
If your yard has a strange shape, divide it into squares and rectangles when you can, marking them off with garden hoses or by spray-painting lines on the ground. Determine the square footage of these sections, then calculate the leftover shapes separately.
Figuring Odd Shapes
With shapes such as circles or right triangles, a little bit more math is involved, although it's not complicated math. For a right triangle shape, measure the length of the two short sides -- in other words, the height and base. Multiply them together -- as if you were calculating a square -- and divide by two.
For circles and partial circles, measure the radius first. For a full circle, start in the center -- or as close as you can approximate -- and measure out to one edge. This is the radius. Multiply the radius by itself, then multiply by 3.14. For example, if the radius is 10, multiply 10 by 10 for 100. Multiply that by 3.14 for 314 square feet. If the shape is only a half circle, measure the radius -- the distance from the straight edge to the outer edge of the circle side -- then follow the same formula. You must divide that square footage in half, however, because you have only half of a circle. If you have 314 square feet in the calculation but it's a semicircle instead of a full one, the square footage is 157 square feet.
If your yard has squares and odd shapes, calculate the square footage of each section separately, then add them together.
Finding Out Sod Thickness
Your yard should be nice and even without sharp drop-offs or high ledges beside driveways and sidewalks. When you prepare your yard for sod, the soil level should be below the level of the permanent structures because sod includes a thin root and soil layer to build the yard back up. Sod distributors use different cutting heights, so ask how thick the sod is before you remove soil from your yard. Thin-cut sod typically has a root layer of 3/4 inch or less, while thicker cuts range from 1 to 3 inches.
Preparing for the Sod
After you know how much sod you need and how thick it is, ask the manufacturer's representative how he sells the sod pieces. Many sell the sod in rolls, often ranging from 10 to 14 square feet each. Divide your square footage by the roll size, such as 314 square feet divided by 10 -- you need 32 rolls in this example. Some sell the sod as square yards rather than square feet, which means you must divide your square footage by 9 to discover the square yardage. Distributors often deliver large sod orders on pallets, so ask how many rolls fit on a pallet. In part, this depends on how thick the sod is cut and the roll length. This number varies, but it's essential to know how many rolls per pallet so you know how many pallets to order. For example, if there are 10 square feet in a roll and 70 rolls per pallet, each pallet of sod covers 700 square feet of space.