A concrete driveway should last for decades if it’s properly installed. Good finishing techniques will make a slab look great for a while, but proper ground prep will keep it looking that way over its lifetime. Here are some great tips on how to prepare the site for a pour.
A good base is everything!
Concrete will crack and crumble if it’s not poured over a solid, stable base. Bringing in 4 to 6 inches of a good compact-able base is a good rule of thumb, but the exact amount of base for your driveway depends on the condition of the existing soil, the climate, and what you plan to park on your driveway.
You may be able to pour directly over sandy or gravelly soil without bringing in any additional base. But if you live in a cold climate, are pouring over heavy clay or organic soil, or plan to park heavy vehicles on the driveway, you may want to increase the base layer to 10 or 12 inches.
The best way to find out how much base you need is to contact the nearest concrete supplier. If you explain your soil conditions and the slab’s intended use, the supplier should be able to recommend the proper base depth and the type to use and provide contact info for a nearby base supplier. Your municipality may also have a handout of recommended base depths in your area.