Concrete foundation, such as those for a wall or a slab foundation, can be built by using forms to set the correct size. A foundation can be built for many types of structures, such as a garage or even a shed in the back of your yard. Building a concrete foundation will require you to create a design plan and then determine where the foundation will be located.
Draw a diagram of how the foundation should look on a piece of paper. Indicate the dimensions of the width and depth of the foundation.
Measure the width and length of the foundation with the tape measure and mark the location of the corners with stakes. Tap the stake into the ground with the hammer.
Mark the outline of the foundation with string. Tie string to one of the stakes and run it to another stake that is on the same line. Repeat this process until you have created an outline around the perimeter with the string.
Dig a trench around the inside perimeter of the string. The depth of the trench should match the depth for the foundation. You can also excavate the entire area within the string to the depth of the foundation.
Level the entire area, especially the trench area for the foundation, with a rake. Compact the entire area by using a plate compactor.
Determine the width for the foundation and create a form using 2-by-4-inch boards. Create one side of the form by placing 2-by-4 boards along the outside perimeter. Use a tape measure to find the required width and create the inside of the form.
Pour concrete into the forms and use a trowel to smooth it out. Let the concrete set for two to three days to harden and then remove the forms.
Attach the corners of the inside of the form with nails using the hammer. Plate compactors can be rented at your local home improvement store.