Driveway cracks, sounds hollow
One common occurrence I have found several times in this situation is when a drain line (usually a storm water drain of some sort) runs under the concrete and has a hole or a bad joint in it allowing water to exit and re-enter the hole taking some of the dirt with it. This will cause a void under the concrete over time and until it is repaired will continue to worsen. This is only one of many possibilities though. If there is a downspout drain or any other type of drain that you know of in the immediate vicinity it would be a very distinct possibility.
good luck !
- 15 Old House Features We Shouldn't Abandon
- 17 Tiny Bathrooms We Love
- 16 Designs for a Low-Cost DIY Coffee Table
- Insanely Easy 60-Minute Home Improvements
- 12 Sheds You Could Live (or Work) In
- Assembly Required: 15 DIY Kit Homes
- 30 Things Every Adult Should Know How to Do
- 10 Surprisingly Simple Woodworking Projects
- 7 Surprising Other Uses for Mayonnaise
- 9 Ways to Make Your TV Look at Home
- 9 Totally Amazing Mobile Home Makeovers
- 8 Cleaning Mistakes Everyone Makes
- 10 Insanely Creative Shelves You Can DIY
- 10 Bargain Organizers for a Tidy Garage
- 7 Easy Budget-Friendly Backyard Makeovers
- 9 Backyard Fire Pits You Can Afford
- 10 Things You Didn't Know Windex Can Do
- Watch These 10 Home Trends Take Off in 2015
- Surprisingly Simple Woodworking Projects
- 16 Garden Borders You Can Make—Easily!