Sinkholes that swallow up cars are fascinating. Weird news columns are filled with those tales. Sinkholes that appear in your driveway are just annoying. At first the problem may seem cosmetic, yet can quickly become a hazard. These divots and pockmarks make people trip, cyclists stumble and drivers lose control. Homeowners who live in geological areas prone to sinkholes will want to take action before problems develop or get too far along.
Why do sinkholes appear? Water erodes sediment and stones. Ground filled with carbonate rock like gypsum and limestone is a major candidate for the mysterious cavities. If you want to learn more about the terrain your home is on you may want get help from residential surveyors. They can give you a better sense of density of the ground beneath your driveway, point out potential problems, and recommend the best areas to repair.
Once you’re ready to redo your driveway, you’ll need to have or rent equipment and buy fill. Smaller jobs can be fixed with asphalt patch, a pothole tamper and a flame torch. Larger problems may require an asphalt saw and small bulldozer. Be warned: If you have a larger job, you should probably hire professionals to ensure safety and a proper repair.
Prepare the Area
Before you actually carry out repairs on the asphalt, remove all dirt and vegetation. You do not want there to be any items nearby that could stick to the asphalt patch. Larger problems that are close to underground wiring or piping may require installing protection. If a sinkhole has opened up near the foundation of a house, you should contact a building inspector. Architectural supports may also be necessary to keep parts of the house from being damaged. Before fixing the hole, you may want to monitor it a little while to ensure it isn’t getting larger.
To repair the entire hole, remove some of the area around the edges. Bigger jobs can require cutting away a section of the asphalt.
Solidify the Ground
Using a pothole tamper or motorized plate compactor, condense and test the area underneath the hole to ensure its solid. If your sinkhole is deeper than four inches, filling the base of the gap with concrete will create support.
Heating up the asphalt around the area of the patch will help the new and old materials adhere to each other. Pour in the asphalt material and spread it out either with a hoe, rake or other similar tool. You’ll want to pour in enough material so that it piles up about two inches above the current surface area.
Now comes the fun part. Use the pothole tamper or motorized plate compactor, pound the asphalt patch until it's fully compacted into the hole. Some DIYers like to put a piece of plywood over the patch and then drive over it a few times to compact the material. After the new asphalt is compacted, remove any excess with a shovel. If you don’t, you’ll end up with a driveway full of bumps. Now double check the instructions and allow the patch to set. If you’re unsure about completing the repairs yourself, there’s no shame in hiring a professional to fix your driveway.