How Thick Should A Concrete Driveway Be

Are you looking forward to a successful concrete driveway installment? When it comes to important concrete projects, the planning part is always important. By doing the project planning part properly, you are able to eliminate the potential problems that you may encounter along the way of construction. So, let us answer the question of how thick does a concrete driveway really need to be?

When it comes to most concrete driveways, no matter the size of them, the recommended thickness is 4 inches. Although some states may allow a concrete driveway thickness of only 3 inches, it is still not recommended, after all, there’s no reason to go for a thinner driveway is there? Additionally, if you’re planning on using the driveway for heavier vehicles, then it may be best to go for a 5 inches driveway.

Does Increasing the Thickness Increase Cost?

Although the costs of increasing the thickness of concrete from 4 to 5 inches can rise by about 20%, its performance also increases by around 50%. Apart from that, you may also want to consider thickening the edges of the driveway by 1 or 2 inches in order to provide some more proper and additional structural support in the areas that are most likely to be subject to heavy loading. 

If you want your concrete driveway to be completely structurally stable even when taking in heavy vehicles, then the thickened sections should extend in from the slab edge 4 to 8 inches. Along with the thickness, you would also want to consider a proper drainage system, which is recommended to be at least one percent or 1/8 inch per foot.

When you’re planning for a concrete driveway project, the thickness of the concrete contents itself isn’t the only thing you should be worrying about, but as well as the rebar & wire mesh reinforcement. Concrete driveways aren’t completely made of concrete. These rebars and steel reinforcements are the ones responsible for providing additional structural capacity for your driveway. 

They are also very important especially when the slab is exposed to heavy traffic. Keep note that these steel reinforcement will only provide additional structural capacity for your driveway and is especially important if the slab will be exposed to heavy traffic. In other words, these rebar wires don’t prevent cracks but they do hold them together in case they get cracked, meaning they are practically useless until the concrete starts to show some cracks.

How Thick Should Concrete Reinformcements Be

When talking about concrete reinforcements, remember that they can be either wire mesh or half an inch of steel rebar. Professionals would often recommend using wire mesh for driveways that are 4 to 5 inches thick, and rebar for those that are 5 inches or more. During the construction, the contractors would place the rebar in a grid pattern with a spacing between bars of approximately 12 inches. 

Another thing that you should keep in mind while planning your concrete is the subgrade of your concrete driveway. When it comes to proper subgrade preparation, soil composition and compaction are the keys that will provide the concrete driveway with the best and most adequate support. When preparing, make sure that there is even slab thickness, and prevent slab settlement and structural cracking.

Keep in mind that the quality of the subgrade is sufficient, with no soft spots, and instead, replaced with good and reliable subgrade materials, such as gravel or crushed rock. In fact, some homeowners even go as far as getting better quality and more expensive soil for their concrete driveway. 

For some better results, 2 to 8 inches of crushed rock should be used as subgrade material, depending on the degree of expansiveness. In any case, you can even consult a soil engineer if you’re not so sure about your soil quality.

Related: How long do concrete driveways last?