This Affordable Solution Might Fix Sunken Sidewalk Pavers, But There's A Catch

If you have sunken sidewalk pavers, you may be looking for a quick and easy fix. Granted, properly fixing the issue can be time consuming. Repairs can even be costly, depending on the extent of the affected area and whether you hire a professional. So, it may be tempting to go with a DIY approach that is promoted as an easy, affordable option: using cans of spray foam to lift the sunken pavers. While this technique might (emphasis on might) fix the problem, there's a catch. Actually, there are several catches ranging from the ease of use to the duration in which the repairs last.

First, to address the obvious question: will a can of spray foam even lift a concrete paver? The short answer is yes, it will. Professional crews actually use a highly modified version of this method, a process they call polyurethane foam jacking, to lift and level large concrete slabs. However, therein also lies the first catch. Foam jacking is not that simple and may require tools you don't possess. For example, in order to get the foam beneath the pavers, you first need to drill multiple holes through the brick. To purchase or rent the tools you need, you may find yourself laying out more money than it would cost to DIY the repairs the traditional way – that is, removing the pavers and rebuilding the base beneath.

Another issue you will likely run into attempting this method with just a spray can of foam is the inexact nature of it. While professional crews use foam pressurized with pumps and monitored with gauges to know precisely how much product is needed to level out a slab, DIYing it with a spray can relies on guesswork. So, while you may be able to lift your pavers, the odds are somewhat stacked against getting it perfectly level.

Even if you get your pavers close enough to level for your satisfaction, this solution may not last for long. That's because lifting sunken pavers with spray foam does nothing to address or fix the underlying issue that caused the paver to sink in the first place. Even the pros advise that the root cause needs to be solved in order for their repairs to last. Additionally, if poor drainage is what's causing your pavers to sink, using foam may even exacerbate the problem. Since foam does not completely fill all the pockets and gaps under the concrete, using it can result in additional erosion around the patch site without proper drainage.

Finally, even in the best-case scenario, this approach can be messy. Anyone who has used this stuff knows it can be a challenge to keep expanding foam from sticking to unintended surfaces. When spraying the foam into the drilled holes, it will expand out of the top of your sidewalk. So, at the very least, you will need to remove the expanding foam from the pavers. Even after cleaning up that mess, you will still need to repair the holes you drilled and make them blend. In other words, this so-called affordable "solution" often creates more problems than it solves.