Tips for excavating near foundations
If the work you need to do requires excavating near foundations, a basement, walkway, driveway or landscaping, these techniques, tools and machines can help you minimize the damage and make the dig quickly and cleanly.
Before excavating near foundations
The first thing to do, of course, is to contact the local utility providers and have them come out and mark any buried utility lines. Each state – or even some municipalities – has regulations that apply to excavations. Some are very restrictive. Simply call 811 and you’ll be put in touch with a local one-call center to get buried utilities safely marked before you dig.
While you’re waiting for the utilities, discuss the excavating plan with your customer so they know exactly where and how you plan to make the job and start excavating near foundations so they know what to expect. Be sure to tell them if anything will have to be temporarily removed and replaced (fences, shrubs, landscape lighting, etc.). This is also a good time to find out if there are any buried sprinkler lines, electrical wires, or gas lines running to built-in barbeques. Talk to any adjacent neighbors so they’ll know what to expect.
When that’s all done and you’re ready to begin excavating near foundations, start small. If possible, carefully move any bushes or small trees so they can be reinstalled when the job is done. If the customer wants you to, carefully relocate any flowerbeds to an area the homeowner has selected. These also can be replanted when the excavation is complete.
For small to medium-sized excavating projects, next cut and remove the sod in small sections so it can be handled easily. Sod cutters work well for this, but you can also use a simple square-point transfer or sand shovel.
When you begin to dig, whether with a machine or by hand, place the excavated soil on a tarp. This keeps the remaining lawn clean and if you have to move a small pile of dirt later, often you can simply pull the tarp out of the way.
When excavating directly against a foundation, first dig a trench 3 to 4 feet away from and parallel to the wall. Then go back and pull the dirt away from the wall. This will avoid putting too much pressure on the foundation wall.
An often-overlooked area of excavating is compaction of the dirt once the excavation has been filled back in. This can lead to incorrect final elevations, improper drainage and even structural compromises. In addition to using a compactor, you may have to add water to soil that is too dry, add dry material to soil that is too wet, or add a different type of soil to make sure the final compaction results in stable ground with the proper drainage plane. Always remember to compact carefully around structures and foundations, as the vibrations from some machines can literally cause buildings to fall down.
Machines and attachments for excavating
A lot of excavation can be done with hand tools, but if the job is big enough to justify using a machine, a mini-excavator on rubber or steel tracks; a rubber-tired backhoe-loader or a skid-steer loader, which is available with rubber tires or rubber tracks, and the right attachments can save you time. All three machine types and the attachments you’ll need are can be rented from a construction equipment dealer, a rental company or another contractor. In some areas, The Home Depot Rental Centers also rent mini-excavators and skid-steer loaders.
The construction equipment dealer or rental company can help you pick the machine that’s right for the job. Just tell them how deep you need to dig, how wide the excavation will be, how tight the access to the job is, how near you need to get to basements or foundations, and what surface you’ll be traveling on. Both should also be able to give you some operating training if you need it.
Mini-excavators with steel or rubber tracks and skid-steer loaders with rubber tracks apply very low ground pressure and so will do the least amount of damage to a lawn, sidewalk or driveway. Even on rubber tires, a smaller, lighter skid-steer loader operated properly shouldn’t damage a lawn. If you’ll be using a bigger machine, create a path using sheets of plywood and drive over them.
If you need to travel between buildings, through a gate or in other tight areas, a mini-excavator is ideal. Some models even have tracks that can be retracted to get through a door or gate and then extended to provide the necessary ground pressure. If you’ll be working near a structure or tree, get a mini-excavator with zero tail swing. When you swing the boom to dump the load, the tail will stay within the length of the tracks.
After the job, clean all dirt and debris, sweep and hose down paved surfaces, and water the sod you replaced.
811 Call before you dig: How it works
Safe excavating is no accident. You have to know what lies beneath the surface before you dig. To find out, all you have to do is call 811 from anywhere in the country a few days prior to excavating, and your call will be routed to your local OneCallCenter. Tell the operator where you need to dig and the type of work you will be doing.
The OneCallCenter will contact the local utilities, and in a few days, they’ll send someone to mark the approximate location of any underground lines, pipes and cables. When the area has been marked, you can begin digging. However, always dig around the marks, not on them. Some utility lines could be buried at a shallow depth. For more information on 811 or for the number of your local OneCallCenter, visit www.call811.com/state-specific.aspx.
–By Roberto Franco