# landscaping - Knowledgebase Question

Chicago, Il
Question by beverly_west
April 23, 2009
 we want to turn half of our back yard into concrete/patio; 20L X 20W. Due to low budget we're considering buying the concrete blocks;could you give us some idea as to how many we'll need and the other steps we might need to know to acomplish our project. We also have these little weed growing thru out our grass,we would like to get rid of we want to utilize our backyard this summer.

April 23, 2009
 Calculating the number of blocks you will need for your project really depends on the measurements of the blocks themselves. A 20 by 20 foot patio equals 400 square feet. A 12" x 12" block covers an area of one square foot. You will need 400 blocks. The rule of thumb is to order what you need plus 10% extra, in case you have to cut some to make them fit - but make sure you can return the unused material. Other sized blocks or pavers will need new calculations so check with the staff at your local garden center. They have calculation charts for each type brick, paver or concrete block. A weed killer for lawns should take care of the weeds. Best wishes with your project!