How is the quantity of the concrete determined?
Concrete is mainly sold by the cubic yard, in one-quarter cubic yard increments. There is usually a minimum purchase of one cubic yard (from most providers) as smaller batches are sometimes less consistent. All concrete measurements should be converted to square feet as part of the normal measuring process. The actual amount needed is determined by a professional contractor, and is based on the thickness and square footage of the project. It is a common practice to add 10% to concrete orders to account for settlement, spillage and waste. This ensures there is enough concrete at the job site.
