Unlike solid foundations that are completely enclosed beneath the structure, pier foundations consist of a number of single piers or columns onto which the structure in built; the entire area beneath the house or building is open, except for the various piers. Pier foundations are cheaper to build than full foundations of block or concrete. The average do-it-yourself homeowner can install his or her own pier foundations in 1 to 2 days, depending on the size of the project.
Tools and Materials
You will need a number of various tools and materials to complete your concrete pier foundation. The concrete footings should be installed using at least 3,000 psi concrete with fibre. You will need a concrete finishing trowel, a hammer, a 2-foot and 4-foot hand level, a masonry trowel, nylon string, a wheel barrel, a mixing hoe, a 5-gallon bucket, 8-inch concrete blocks, type N masonry mix, marking paint and sand.
Layout and Pour the Footings
Layout the footings and dig them with a shovel and pick. The footings should be 24 inches wide by 24 inches long and 12 inches deep. Find all four corners where the structure will set, mark the corners with orange marking paint, and pull a nylon string to connect the corners. Mark the remaining footings about 8 feet apart along the string; use the string to line up the footings. Use a builder's level to ensure that you have all of the footings dug at the same depth. Pour the pier footings and allow them to set for 24 hours before you lay the concrete blocks.
Installing the Piers
Set all four corner blocks of the pier foundation first. Pull a nylon string from each block corner and make sure they are square and in line with each other. The piers will be 16 inches long by 16 inches wide and what ever height you have determined you want. The average height is usually 32 inches. Apply your type N mortar on the footing, stack two blocks side by side, and then turn the next course (set of blocks) perpendicular to the previous course, with the next two blocks also being side by side.
Make sure to butter all joints with the mortar and trowel, and check and make sure that the pier remains plumb (level on a vertical scale) as you go up. Monitor all the piers so that they all remain in line with each other; use the nylon string as a reference. Continue filling in all the piers until the foundation is complete.