Can You Lay Pavers Over Stamped Concrete That Is Cracked?

Homeowners commonly ask if they can install pavers over cracked stamped concrete. The short answer is yes, you can lay bricks over fractured aggregate. However, before starting this project, some essential things must be considered.

A proper assessment can help minimize further cracking. It should consider fracture severity, repair techniques, and base preparation. Using a flexible joint material between slabs can also help. As a seasoned contractor, I have completed hundreds of hardscape projects. I always tell homeowners that pavers can restore beauty.

However, existing substrate flaws may still show up over time. Managing customer expectations is critical. Implementing preventative measures for drainage and ground movement is also vital. There are also creative ways to incorporate splintering into the block’s design. This creates a stable, unique look. Flagstone can deliver fresh curb appeal to a stamped concrete base, showing its age. With thoughtful design and workmanship, it is possible.

Assessing the Existing Concrete

The first step is to examine the existing stamped surface thoroughly. Determine the extent of the cracking. Here are some key things to look for:

• Number of gaps – Are there just minor gaps or extensive splintering throughout? Minor gaps may be less concerning.

• Fracture width – Are there hairline gaps less than 1/8 inch wide or more significant gaps? Larger splintering is more problematic.

• Fracture pattern – Do gaps follow the pattern lines in the cement? These indicate the concrete may be unstable.

• Spalling or pitting – Are there signs of surface deterioration, like chunks or holes? This can compromise the base.

• Drainage issues – Does water pool on the aggregate instead of running off? Poor drainage accelerates fractures.

Carefully inspect the splinters in the concrete. This will help you gauge whether pavers are a good solution. It will also help you determine if repairs may be needed first.

Why Cracks Develop in Stamped Concrete

Understanding what causes cracks in stamped concrete can provide clues on how problematic they may be for placing pavers. Here are some common reasons fractures occur:

• Settling or shifting soil underneath can cause sinking, tilting, and splitting as the ground moves.

• Freeze/thaw cycles – Water seeping into tiny pores in the concrete can expand when frozen, gradually widening gaps.

• Poor joint spacing – Cement naturally shrinks as it cures. Too much space between joints gives no room for expansion and contraction.

• Excess weight or pressure – This can cause splintering over time. Heavy vehicles, structures, or tree roots are often the source.

• Substandard installation – Weak mix design, inadequate curing, or lack of proper base prep can all trigger fractures.

Ideally, you want to fix the source of the fractures before covering it with pavers. Some gaps may be symptomatic of underlying issues.

Prepping Cracked Stamped Concrete Patio for Paving Stones

Upon inspection, if the fractured aggregate appears reasonably stable and intact, there are a few critical steps for prepping it for pavers.

First, thoroughly clean the existing cement. Remove all dirt, grime, leaves, oil stains, etc., so the overlay bonds properly. Use a degreaser to eliminate oily spots.

Next, repair any substantial gaps or faults. Rout out more extensive fractures with a masonry saw to open them for patching. Fill all gaps with a flexible polymer-modified cement. This helps prevent gaps from telegraphing upwards through the bricks.

Finally, apply a masonry adhesive bonding agent to the cleaned surface. Follow the manufacturer’s instructions. This liquid compound is specially formulated. It helps the overlay bond tightly to the stamped concrete. Allow it to fully cure before placing down the pavers.

Laying Patio Pavers Over An Existing Concrete Slab

Once all prep work is complete, you can put down the pavers. Here is an overview of the critical steps:

• Excavate 2-4 inches deep to accommodate a gravel base layer for the blocks. Tamp down firmly.

• Install edge restraints around the perimeter to contain the stones. These may be concrete borders, plastic edging, metal strips, etc.

• Fill the excavated area with 1-2 inches of coarse sand or fine gravel. Smooth and level the bedding layer.

• Lay the stones in the desired pattern, maintaining even spacing between them. Tap down firmly with a rubber mallet.

• Sweep dry polymeric sand over the surface and into the joints. Spray lightly with water to set the sand.

The base layer beneath the bricks and proper joint sand provide some forgiveness and flexibility. If the concrete below moves, the pavers can shift slightly without fissuring.

Long-Term Pavers Over Concrete Performance Considerations

Placing pavers over stamping that has minor gaps can offer a fresh new look and usable surface. However, it pays to set realistic expectations on the long-term performance.

Existing crevices may gradually show through the pavers over time as they shift. Using a flexible joint material can help minimize this.

Drainage issues will still need mitigation if water pools on the concrete below. Trapped moisture accelerates deterioration. Consider adding a drain tile system.

Prevent heavy vehicles from driving on the stone. This will avoid over-stressing the stamped base. It may compromise the weight limit it can support.

With reasonable precautions, pavers can disguise gaps and restore aesthetic appeal. However, monitoring and maintenance will be ongoing to maximize durability.

Common Mistakes To Avoid: When Installing Pavers Over Concrete

Common mistakes to avoid when putting down pavers over stamped concrete include:

• We need to clean and prepare the existing slab surface thoroughly before installation. The old concrete driveway or paver patio must be free of dirt, oil, grease, and glue. This is necessary for the pavers to adhere using adhesive properly. Failing to do adequate surface prep can lead to the stones becoming unstable over time.

• We must create an adequate drainage layer between the layers using a bedding layer of sand. Lack of drainage can lead to pooling of water and freeze/thaw damage over time.

• The pavers have not been placed to allow proper height transitions from the cement slab to adjacent areas like doors or steps. This can create tripping hazards if not planned for.

  • Not placing proper borders or restraints around the perimeter of the hardscape area can cause shifting. Unrestrained blocks are more likely to move and become uneven.

• Be sure to compact the sand bedding layer before hardscape installation. Lack of compaction can lead to settling issues, causing the pavers to sink or become uneven over time.

Proper planning and preparation of the existing slab are critical. Allow for drainage. Take steps to prevent shifting or settling of the pavers after installation.

Hiring a Professional Installer

Tackling a DIY project to overlay stamped concrete by installing patio pavers has some complexities. An experienced hardscape contractor is well-versed in assessing issues. They are skilled at handling challenges that arise.

Key reasons to consider hiring a pro include:

• Evaluating fractured gaps severity and appropriate repairs

• Handling drainage improvements if needed

• Ensuring proper base preparation and installation methods

• Accessing specialized tools like plate compactors

• Providing experienced guidance on products and patterns

• Delivering consistent, professional results with warranty

DIY projects can save money. However, hiring an expert installer to protect your investment may be worth the cost. They also handle all demolition and hauling of old materials.

Conclusion

Installing a border paver system over fractured stamped aggregate can refresh the look of aging hardscapes. With careful inspection, prep, and best practices during installation, patio pavers on top can mask existing gaps. However, the longevity of the surface depends on the severity of splintering, drainage, and monitoring for issues over time. Consulting a professional provides experienced tips on learning how to overlay concrete with paving stone guidance.

 

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