House with curved driveway  Howard Sandler

Pouring Concrete?

How to Measure your project.

If you made to junior high math chances are somewhere along the way a teacher probably showed you how to figure out the area of a rectangle. What do you do if your new driveway or concrete project isn't going to be a simple rectangle? Relax, I'm going to show you the easy way to figure out the concrete's square footage. You won't even need a calculator this is so easy. All it takes is a sheet of graph paper and a few colored pencils, You just need two colors so there is no need to run out to the store.

If you don't have any graph paper you can print your own. Just follow this link: Print Free Graph Paper at home. I would suggest four squares per inch in a dark color, but you can use whatever size you want.

wireframe sketch of U-shaped driveway pavement layoutFor our example, picture a U-shaped driveway with a wide path leading back to a garage and a second smaller path connecting to a front porch. In the image to the right, the purple and blue represent the garage and house respectively. Green is the lawn area and white is where the new pavement is going to be laid. This is the kind of problem that would be difficult even if you know how to do the math.

sketch of shaped driveway transferred to graphpaperIn order to figure out the area of your driveway you will need to transfer a sketch of it onto the sheet of graph paper. Just take a measuring tape and measure the area where the driveway will go. Then draw it onto the graph paper so that 1 foot in the real world is the length of one square on the paper. The image on the left is what our sample looks like on the graph paper.

what the grid looks like after coloring inGo through the drawing and color in all the squares that will be pavement. If the square is going to be all paved or more than half way paved, make it one color. (red in our example) If the square will be less than half paved make it the other color. (blue in our example) Squares that will not have concrete in them leave white. Once you have colored in all the concrete area on the graph paper you are ready to figure out the square footage.

To calculate the total footage you need for your project all you need to do is count up the squares. Add 1 square foot for each red square and half a square foot for each blue square. In other words, for every two blue squares you add only one square ft. Don't add anything for the blank white squares. You've proably figured out this won't be 100% accurate. Believe it or not, thats a good thing. What will happen is that you will end up with just slightly more concrete than you need. Not by much, but just enough that you won't have to run to the hardware store at the last minute to finish the job. Anyone can tell you having a bit too much concrete is way better than running out right at the end of a job.

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