# How to Estimate the Cost of Painting for a Water Storage Tank

Painting contractors often give wildly different estimates when asked to bid on a specific painting project. It is for this reason that many people choose to forgo the hiring of expensive professionals and do the job themselves. In this case, the only costs they incur have to do with the purchase of the paint. Because paint, too, can be expensive, it's best to buy the exact amount you need. This figure can be difficult to generate for inexperienced painters. If you need to estimate the cost of painting a water storage tank, you'll need to figure up the exact surface area in square feet.

1. Measure the radius of the bottom of the water storage tank (radius = the distance from the center of the tank to the outer edge).

2. Measure the height of the storage tank on one side.

3. Multiply the number from Step 1 by itself.

4. Multiply 2 times 3.14 times your result from Step 3.

5. Multiply 2 times 3.14 times your result from Step 1, times your result from Step 2.

6. Add your result from Step 4 to your result from Step 5 for the total number of square feet.

7. Check the label on the gallon of paint for the exact number of surface area coverage in feet.

8. Divide your result from Step 6 by the number from Step 7 for the total amount of gallons you will need to buy to paint your water storage tank.