Should You Overlay or Replace That Cracked Concrete Surface?

First Federal Savings Bank, Sheridan, Wyo., asked Doug Carlton if there was an overlay that could improve their cracked, uneven parking lot. He told them no. The crack pattern shows a problem beyond random cracking. He guessed that the concrete is too thin or not properly reinforced, or that the subgrade had failed. Photo courtesy of Doug Carlton

The question “to overlay or replace” is more complex than some will admit. Unfortunately, the decision is often left to you, the decorative overlay professional. 

Most of you will be surprised by my opinion as to why so many overlay projects fail even as our overlay material options continue to improve. Need I remind you what can potentially happen when the substrate beneath your new work of art fails? Nothing will undermine a customer’s confidence quicker than overlay delamination. This is not the type of exposure most decorative professionals need, ever. 

While preparing to write this article I researched the life cycle, or life expectancy, of a typical modern-day slab of concrete. My hope was that an engineer somewhere had compiled the data you could use as a do-or-don’t rule of thumb. Sorry, no such luck. What I found is that each potential concrete canvas has its own variables that will affect whether or not an overlay is recommended. 

Many of these variables hinge on good concrete practices at time of concrete placement, and who honestly knows the level of effort exerted decades ago? In most cases the only information you get is by evaluating the concrete’s surface. Each person contemplating their next overlay project must use due diligence before making such a big commitment.


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