Cracked concrete sidewalks are a common sight in many USA communities. They can be unsightly, pose a tripping hazard, and allow water to seep in and cause further damage. If you’re a homeowner or property manager dealing with concrete sidewalk repair, this guide is for you.
This article will provide a comprehensive overview of concrete sidewalk repair, including:
- The different types of concrete sidewalk cracks
- Causes of concrete sidewalk cracks
- How to assess the severity of concrete sidewalk cracks
- DIY vs. professional concrete sidewalk repair options
- Steps involved in professional concrete sidewalk repair
- Preventing future concrete sidewalk cracks
By the end of this article, you’ll have a better understanding of how to fix concrete cracks and keep your property safe and looking its best.
Types of Concrete Sidewalk Cracks
Concrete sidewalk cracks can vary in size, depth, and severity. Here’s a breakdown of the most common types of concrete sidewalk cracks:
- Hairline cracks: These are thin cracks, typically less than 1/4 inch wide, that may appear like spiderwebs on the surface of the concrete. Hairline cracks are often considered cosmetic and may not require immediate repair.
- Slip cracks: These are narrow cracks, typically between 1/4 inch and 1/2 inch wide, that run along the surface of the concrete. Slip cracks can create a tripping hazard and should be repaired.
- Expansion cracks: These cracks are caused by the concrete expanding and contracting due to temperature changes. They are typically straight and follow a control joint, which is a pre-made groove in the concrete designed to relieve stress and prevent random cracking. Expansion cracks are usually not a major concern unless they are wider than 1/2 inch.
- Settlement cracks: These cracks are caused by uneven settling of the soil beneath the concrete. They can vary in width and depth and may be accompanied by uneven slabs of concrete. Settlement cracks can be a sign of a more serious foundation problem and should be evaluated by a professional.
- Heave cracks: These cracks are caused by the concrete slab pushing upward, often due to expansive soil conditions. Heave cracks can be uneven and accompanied by raised edges of concrete slabs. They can be a sign of a serious foundation problem and should be evaluated by a professional.
Causes of Concrete Sidewalk Cracks
Several factors can contribute to concrete sidewalk cracks, including:
- Improper subgrade preparation: The subgrade is the layer of soil or gravel beneath the concrete slab. If the subgrade is not properly compacted or leveled, it can settle over time and cause cracks in the concrete.
- Poor concrete mix: Concrete that is not mixed properly or does not have the right proportions of ingredients can be weak and prone to cracking.
- Temperature fluctuations: Concrete expands and contracts with changes in temperature. Extreme temperature swings can put stress on the concrete and lead to cracks.
- Tree roots: Tree roots can grow under sidewalks and push up on the concrete, causing cracks.
- Improper drainage: Poor drainage can allow water to seep into the soil beneath the concrete and cause it to wash away, leading to settlement and cracks.
- Overloading: Concrete sidewalks are designed to withstand a certain amount of weight. Overloading a sidewalk with heavy vehicles or equipment can cause it to crack.
- Age: As concrete ages, it naturally deteriorates and becomes more prone to cracking.
Assessing the Severity of Concrete Sidewalk Cracks
Not all concrete sidewalk cracks are created equal. Some cracks are merely cosmetic and can be left unrepaired, while others require immediate attention to prevent further damage. Here are some factors to consider when assessing the severity of a concrete sidewalk crack:
- Width: Wider cracks are generally more serious than narrow cracks. Cracks wider than 1/2 inch are typically considered to be structural and should be repaired.
- Depth: Deeper cracks are more likely to allow water to seep in and cause further damage. Cracks that extend more than halfway through the depth of the concrete slab are considered to be structural and should be repaired.
- Movement: Cracks that are moving or expanding are more serious than stable cracks. You can check for movement by marking the crack with a pencil and monitoring it over time.
- Location: Cracks located near the edges of a sidewalk slab are more likely to cause the slab to crumble and should be repaired.
