The cost of concrete significantly impacts the price of a construction project because large quantities are sometimes needed to construct walls, foundations, driveways, sidewalks and other structures. Pricing concrete requires you to measure the size of your construction project and calculate the cubic yards of material needed. When you know the concrete requirements to complete the project, you can contact suppliers for quotes. You can also estimate the cost of concrete using "ready-mix" bags.
Measure the size of your construction project. If you are pouring concrete for a foundation, patio, driveway or other surface, use a tape measure to find the project's length, width and thickness. Include any measurements for walls and support beams.
Calculate the square footage. For example, if you are pricing concrete to pour a driveway, multiply the driveway's length times its width. For a driveway measuring 20 feet long by 15 feet wide, this equals 300 square feet.
Calculate cubic feet. For the driveway example, the depth will be four inches. To convert inches into feet, divide four by 12 (12 inches in one foot). This gives a value of 0.33. Calculate cubic feet by multiplying the driveway's square footage or 300 times 0.33. This yields 100 cubic feet.
Find cubic yards. Divide the cubic feet by 27, as there are 27 cubic feet in 1 yard (3 x 3 x 3). The driveway would have 3.70 cubic yards (100/27). Since concrete is ordered from a supplier by the cubic yard, round up to four cubic yards. This is the amount of concrete needed.
Call your local concrete supplier to obtain quotes. Provide the number of cubic yards. The average price of concrete, as of 2010, was between £78 and £97 per cubic yard for full truckloads of 10 cubic yards delivered to the job site, according to "Today's Concrete Technology."
Purchase concrete from local home-improvement stores. If your concrete project is small, you may be better off purchasing concrete in 40-, 60- or 80-pound "ready-mix" bags. While you will have to mix the concrete yourself or pay someone to do it, it may save you money. As of 2010, an 80-pound bag of concrete cost £2.20 to £2. A yard of concrete or 27 cubic feet equals 90 40-pound bags, 60 60-pound bags and 45 80-pound bags. For the aforementioned driveway example, four cubic yards of concrete are needed. This equals the following totals, using 40-, 60- and 80-pound bags respectively: 360 bags (90 x 4), 240 bags (60 x 4) and 180 bags (45 x 4). If an 80-pound bag is priced between £2.20 and £2, the cost would be £409 to £468 for one cubic yard of concrete. In this case, it is cheaper to order the concrete from a supplier.
When calling concrete suppliers, ask if there is an order minimum. Some suppliers will only deliver if you meet that minimum. The above calculations do not factor in any concrete waste. Mistakes or unforeseen circumstances may require you to add extra concrete to your calculations. Adding an extra cubic yard accounts for this.