The 4000 PSI mix is the most common for both residential and commercial projects. This mix can be used for everything from driveways to sidewalks and foundations. When properly placed and cured this mix will develop a strength of 4000 pounds per square inch (PSI) or more. However, depending on strength requirements and exposure to the elements, 3000 – 3500 PSI mixes are also available. If you are unsure which mix to use please feel free call any of our plant managers. They will be glad to talk about your project and discuss your options.