Seeing discoloration or fine, hair-line cracks on your concrete driveway is already a cause for concern, especially if your paving is just a few years old. What more if you start noticing spalling, unleveled sections, and big cracks; you just might snap and go through the roof! You’d start asking yourself what had gone wrong. Was the concrete thickness not enough? Should you have spent a bit more for a thicker one fo your home patio or driveway? But more than that, how do you know how thick of a slab to use for your driveway?
As Duke City dwellers, we all know how keeping up with Albuquerque’s climate and caliche is a real struggle. Though we enjoy the 310 days of sunshine, the scorching summers can be nasty. There’s also the caliche in our soil that shifts, expands, and contracts depending on the moisture level it is exposed to. Let’s try to understand it a bit better.
- Summer Heat + Afternoon Downpours: Intense heat, especially in summer, causes concrete to expand. As temperatures rise, its molecules spread out, creating internal pressure. It only stops expanding when it reaches a thermal equilibrium with its surroundings. The problem is when it rains, the temperature suddenly drops, and the concrete then contracts. This change adds more stress to the structure. If this goes on continuously and there are no adequate expansion joints to let concrete breathe when it expands, cracking is inevitable.
- Winter Freeze-Thaw Cycles: Our winters are mostly mild. Although, admittedly, there are freeze-thaw cycles that happen from time to time. Now you might think low temperature is okay since it won’t cause concrete to expand, but it does not help at all. Remember that concrete being porous, allows water to pass through it. When the temperature drops, the moisture inside concrete will freeze and exert internal pressure. When the temperature rises, it will turn back into water and go further down until it reaches the rebars causing the metals to corrode. This leads to surface scaling, spalling, and cracking.
- Caliche: This hardened layer of calcium carbonate is found beneath the surface. By itself, caliche is rock solid and stable. However, the same can’t be said about the dirt around it. When the land around it gets wet, it could contract, causing instability. On top of that, caliche’s rigidity prevents water from passing through, causing water to pool which could lead to erosion.
- Soil Composition: Albuquerque's soil is a mix of clay and sandy loam. This poses challenges when constructing hardscapes. Clay is stable when it has the right amount of moisture. But once it gets too wet, it becomes soft, when too dry, it can crack. It’s also terrible for draining water. Meanwhile, sandy loam, though superb at draining water, does not provide a stable sub-base. Moreover, it lowers the ability of concrete to bond with the ground.
Now that we have a better understanding of how Albuquerque’s climate and topography, let’s now check the other determinants of how thick your concrete should be. As you already know, knowing the right thickness can prolong the lifespan of your driveway.
Understanding the Factors
- Expected Load: How do you intend to use your driveway? Are you planning on simply parking a single SUV? How about more than one pickup truck? Do you wish to park an RV in your driveway or store heavy machinery in there? For residential driveways that typically handle passenger vehicles, they require a 4-inch thick concrete. However, if you are expecting to frequently park trucks, RVs, or other heavy commercial vehicles, it is best to use thicker concrete for it to be able to carry heavier loads without getting damaged.
- Driveway Size and Slope: For a larger concrete driveway, you can use a standard 4-inch concrete. This is because a larger surface distributes weight more evenly, and no single point gets to bear heavy loads at a time. However, when dealing with steeper slopes, you may have to use a thicker slab for added support. Doing this will provide ground stability and prevent erosion.
- Bearing Capacity: Albuquerque has different types of soil. Clay tends to shift and expand when wet. Using a thicker concrete base can help mitigate these issues. If you are unsure of the type of soil you are dealing with, you can have your property tested. Doing this can provide valuable insights into your specific soil conditions.
- Local Building Codes: Albuquerque, like other cities, have building codes and regulations when constructing concrete driveways. To avoid problems with your concrete project, check with the city's building department to make sure you are in compliance.
How Thick Should Driveway Made of Concrete Be?
While these are general guidelines, it's essential to consider the specific factors mentioned above:
- Residential Driveways: Standard 4-inch thickness should suffice for lighter passenger vehicles. However, if the soil condition is particularly challenging or you are planning on driving heavier vehicles over it, we recommend using a 5 or even 6-inch thick concrete for stability.
- High-Traffic Areas: For driveways that experience frequent heavy use, such as those leading to garages or workshops, consider a thickness of 5 to 6 inches. Adding extra inches can give your paving the additional strength it needs to carry heavy loads without cracking or deteriorating prematurely.
As a Burqueno you might want to DIY the installation of your concrete driveway. However, for safety reasons, it is best to have a professional do the installation for you. They are best equipped to handle different types of soil and can determine the right thickness depending on different driveway usage and climate challenges.
Added thickness is not the only thing your driveway needs. You also need to give it a little bit of TLC if you want to make sure it stays gorgeous and useful for a long time.
- Proper Curing: Allow your concrete to cure completely before exposing it to heavy traffic or water. In 24 to 48 hours, after initial curing, you should be able to use it for foot traffic. Wait for at least a week before using it for lighter cars, and 28 days for it to reach its full strength before driving heavy cards or machinery over it.
- Sealing Your Driveway: Applying a high-quality sealant protects your concrete from stains, UV rays, and de-icing chemicals.
- Regular Inspections: Keep an eye out for cracks, spalling, or uneven settling. Early detection is key.
- Repairing Damage: Small cracks can be repaired with a concrete patching compound. For larger issues, consult a professional.
If you need to install a concrete driveway call the best concrete contractors in Albuquerque, New Mexico!
