Thursday, December 10, 2009
Digging out a crawlspace - Dirt Extraction
We run into crawl spaces often that have only 8 to 12 inches of clearance between the floor joists and the ground, and in some homes, the joists are only inches from the ground floor of the crawl space. There are several problems with this scenario, but the biggest problem would be that there is not enough space to inspect for plumbing leaks, termites, and water intrusion. There is a remedy to tight crawlspaces, but it isn't easy.
Digging out a crawlspace to within 18"-24" of height clearance is a specialty of ours, but if you want to attempt to save on the cost of paying a contractor to dig the crawlspace out for you, I will give you some tips.
You will need at least 2 to 3 workers or more every day that you are excavating the crawlspace. This is not a solo project. There are several ways to pull the dirt out of the crawl space. Since you will likely have limited resources, you will look at sledding the soil out or renting a conveyor. One to two workers inside will load the soil onto the sled or conveyor, and the other person will wait outside to dispose of the soil as it comes out. This is grueling, hard work so be prepared for it before starting.
Now for some technical aspects on extracting soil from the crawl space. You cannot just dig wherever you please. There are footings under the outside foundation wall that cannot be undermined by excavating to close to them. The challenge is that you have to leave the soil that your footings bear on alone. Loads transfer from the footings are straight down and at 45 degree angles to the sides. Therefore, you cannot remove the soil that falls in that 45 degree line from the underside of the footing. The same applies for the footings that the piers or columns sit on that hold up the main beams or girders of the home. Depending on the depth you are excavating determines the amount of space you will need to leave undisturbed out away from the walls and piers. For a safe estimate, come out away from these footings the same distance that you are excavating. So, if you are trying to dig out 18" of clearance between the joists and the ground, come away from the wall and footings 18". We could excavate closer to the walls and footings, but I'm not comfortable recommending anything more than that without seeing the crawl space.
It is possible to support the middle of the home, excavate the entire crawlspace, and add new footings and support piers after the crawl space has been completely dug out, BUT this should be done by a certified technician.
If you are interested in digging out your crawlspace, please give us a call @ 1-877-409-2837 or SIGN UP online for a FREE ESTIMATE. We service all of Indiana, Ohio, Kentucky, and Illinois.
Thanks for reading the rambling thoughts of a crawlspace inspector,
Larry Ralph Jr.
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