For do-it-yourself landscape projects, a few basic math skills will go a long way toward making the end result a financial and functional success. Estimating the right amount of materials to buy may seem tricky, but with a little guidance and knowledge, you can soon be estimating like a professional contractor. Figuring out how many patio pavers or brick to buy for a walkway or patio is a good place to start.

What is the Size of Your Project Area?

First, you need to know the size of your walkway or patio as measured in square feet. A 12 inch by 12 inch space equals one square foot. Therefore, an entry walk to your front door that is 50 feet long and four feet wide will be 200 square feet. A 10 foot by 12 foot patio space is 120 square feet. It is usually a good idea to round up your numbers slightly. A 195 square foot project can be rounded up to 200 square feet; 487 should be turned into 500.

concrete brick paver sizeHow Large Are Your Pavers?

Square and rectangular pavers, whether they are bricks, concrete interlocking pavers or flagstone, are the easiest to estimate. A standard paving brick is typically 4 inches by 8 inches. It takes four and a half bricks to fill a one square foot area. To estimate the total brick quantity needed, multiply your project area size in square feet times 4-½. Your 200 square foot walk will need 900 brick pavers.

Most concrete rectangular concrete pavers are the same size as bricks, but there are many other sizes and shapes of interlocking pavers available. Verify the size of the pavers with your landscape materials supplier. They can tell you the correct pavers per square foot number to use.

Flagstone and slate pavers with irregular shapes are a little more difficult to estimate. Again, your supplier will be able to tell you a reasonable number for estimating based on the average size of the flagstone. When working with irregular shapes, it is best to leave a larger margin of error than you would with rectangular pavers.

concrete unit patio paversContingency Factors

Professional landscape estimators and contractors always use a contingency factor when they total up their numbers. This allows for minor changes in design that often happen when you install a project, as well as minor mistakes in estimating. When you actually order your landscape construction materials, order about 10 percent more than you estimated. This allows for a few broken pavers during the course of the project and will also give you a small stockpile of extra materials in case you need them for replacements or future changes to your paved area.

Be aware that you may not be able to get the exact quantity you want. Patio pavers typically come in bound cubes on pallets. While you can often order a half cube, other divisions in size may not be possible. You may have to order more pavers than you had planned. That gives you the chance to make your project larger or save more materials for the future.

Once you understand the concept of square feet and the relative size of different pavers, it is fairly straightforward to figure out how many brick or flagstone you need for your patio. Just remember to double and triple check the size of your area and all of your calculations. It is easy to get a couple of numbers switched around and end up with half as many or twice as many pavers as you need!