A concrete foundation pier can be purchased at almost any lumber yard and home improvement center around the world. They are usually about 12 inches tall and their base is usually about 12 inches wide and works its way up, to a 6 inch square at the top and this usually has two metal brackets sticking straight up out of it. These metal brackets can be nailed onto the post that will be supporting the floor framing.
There are plenty of homeowners, handyman and even some contractors who set these concrete piers directly on the soil, with out any support from a concrete footing. Over time, if a concrete footing is used, the foundation pier could actually provide little support for the floor framing components.
Here is an example of what I’m talking about. You have a section of your floor that is sagging and you need to raise it and install additional support underneath these areas to fix the problem.
When you crawl under the house, with your jack and new concrete foundation piers, you notice the floor framing has a cracked support beam. Instead of replacing the beam, you simply jack up the floor and install two foundation pier supports underneath the damaged wood beam and set them directly on top of the soil.
There is a good chance, over time, that the weight of the house will push the concrete piers into the soil and you will now be back to square one.
Here’s the solution to your problem, most of the time. Pour a 12″ x 12″ wide and 12 inch deep concrete footing underneath the area where the new piers will be installed. This will provide you with the additional support necessary, most of the time.
To repair your home properly, you would need to contact a building professional or a structural engineer to provide you with the exact specifications of building materials and requirements for your new footing.
In other words, it’s not really a good idea to set a concrete foundation pier directly on top of the soil.
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