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How to Measure a Swimming Pool

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Measuring a swimming pool is necessary for two reasons. The first is to calculate the water volume in the pool. You will use this number frequently when adding chemicals to the pool water as many of the chemicals depend on the amount of water in the pool. The second reason for measuring a pool is to determine the square feet necessary for replacing a pool liner. When taking these measurements, you will most likely need a friend to help you with the tape measure.

Pool Volume

Measure the pool’s length and width. Take the measurements by holding the tape measure at the two points farthest from each other on the length and width of the pool.

Calculate the average depth for the pool. For example, add the shallow end figure (3 feet) with the deep end figure (9 feet). Divide by two, which will result in an average depth of six feet.

Multiply the length times width times average depth. For rectangle, square or custom-form pools, multiply the figure by 7.5 to compute total water volume in gallons; multiply round or oval pools by 5.9 to compute total water volume in gallons.

Measure An Above-ground Swimming Pool

An above-ground pool is an excellent option for those who would like the availability of a pool at home without the high price tag of a more permanent in-ground pool. Above-ground pools are widely available in three different shapes: circular, oval and rectangular. Carefully measure the length, width and height of your pool easily and without error. Measure the height of your above-ground pool's walls. Take the tape measure and place the end firmly at the bottom of the wall. Measure the width by placing the end of the tape measure on the top and in the middle of one of the pool's long walls and drawing it across the top to the end of the opposite wall. The tape measure should cross the direct center of the pool.


For odd shaped pools, you can contact a pool supplier for tips on measuring your pool. Pool suppliers may also offer free measuring to help you determine the size of your pool.

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