Concrete 101: Shrinkage & How to Mitigate It

Concrete may look solid, but as it cures and dries, it actually changes shape slightly. This process is called shrinkage — and if not managed correctly, it can lead to cracking.

Types of Shrinkage

Drying Shrinkage: Happens as moisture leaves the concrete over time.
Autogenous Shrinkage: Occurs in low water-to-cement mixes as the cement particles consume water during hydration.
Plastic Shrinkage: Early cracking that can occur while the concrete is still fresh, especially in hot or windy weather.

Ways to Reduce Shrinkage

Proper Curing: Keeping the concrete moist (with curing compounds, water spray, or coverings) helps reduce early shrinkage.
Control Joints: Planned cuts in the slab that allow cracks to form in controlled, less noticeable spots.
Balanced Mix Design: Using the right water-to-cement ratio and sometimes adding shrinkage-reducing admixtures.
Fibers: Tiny reinforcements that help hold the concrete together as it shrinks.

Why It Matters

Shrinkage is a natural part of concrete’s life cycle, but smart planning and the right techniques can keep cracks from becoming a bigger issue.

👉 Cracks may be common, but with proper care, they don’t have to be costly.

⚠️ Legal Disclaimer:
This blog post is intended for informational purposes only and should not be taken as professional, legal, or construction advice. Every project is unique, and conditions may vary. RLW Concrete LLC is not liable for any actions taken based on this information. Always consult with a qualified professional or attorney for your specific needs.
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