During the patio planning process, optimum paver installation options cover a wide range of possibilities. As you look around established neighborhoods in Madison WI and throughout the area you’ll see a trend that’s been popular for decades – a poured concrete slab behind the house to serve as a patio. Long before the idea of outdoor living spaces and comfortable hardscapes was accepted, builders “put in a patio” for homeowners.
Traditional, gray concrete is relatively inexpensive and has proven to be versatile. But after years of exposure to Wisconsin’s weather they need work. Most are drab, many are cracked and homeowners are looking for alternatives.
Among the most popular hardscape options is the use of paver bricks, paver blocks and stone. Replacing an existing patio with one of these choices is at the forefront of patio planning. The concrete slab can be tinted, colored and textured. But, if a complete hardscape is planned, matching the paver installation on the patio to walls, steps, fire pits, walkways and paths makes sense.
Existing Concrete as Paver Installation Base
Patio planning is more than deciding how big and what shape. Drainage, settling, cracking and shifting are all considerations that have to be in the formula. To bring your existing concrete patio into the 21st century and blend it with your paver or stone outdoor living space you can install pavers directly on top of an existing slab. This is not the most recommended solution, but it can result in a successful paver patio.
With the right preparation, a concrete slab can hold a paver patio. Making use of this base saves the cost and disruption of breaking up and tearing out the old concrete. The first step in deciding if this is the correct move in your patio planning process is to check for cracks, chips and shifts in the concrete slab. If the concrete is in good shape, most paver suppliers say preparation should be much the same as if putting the pavers on the ground. To avoid the added cost and labor of using mortar, lay down a ½- to 1-inch bed of course sand and firm it in place – just like a traditional paver installation.
Minimize Potential Problems
Evaluating an existing concrete patio as a base for new pavers, putting in the right base and heading off potential problems makes this a job for professionals. During your patio planning, consider these factors required for a paver installation you’ll be proud of:
- Drainage – when pavers are installed over concrete, rain water and melting snow has nowhere to drain into the ground. It will run off. The first critical step to a successful installation is making sure the concrete is sloped properly – away from the house – and rain doesn’t puddle in spots. Make sure that any sand base that’s added maintains the correct slope and accounts for any low spots so water works its way through the pavers and off the patio.
- Changes in height – when you add pavers on top of concrete the overall height of the patio, walkway or steps goes up by 3 inches or more. This change has to be considered when doorways, steps and built-ins are part of the patio planning effort.
- Sand in the joint – the seams between pavers will be filled with polymeric sand to keep them from shifting. When it’s set the sand allows water to filter through and run off.
- Mortar? – a paver patio or walkway installation secured with mortar makes sure the pavers don’t shift when put down over a concrete slab. It’s a potential option for a solid installation. In some cases contractors may select a combination of mortar and adhesives rather than edging to hold pavers on the end in place – this method can cause water to puddle under the pavers.
- Appropriate Edging – a paver patio on top of a concrete slab needs a firm edge. The edge material has to allow water to drain. If it’s watertight puddles can form an create drainage issues.
Combination Outdoor Living Spaces
One of the nicest things about a paver installation over the top of a concrete slab is that it makes it easy to blend with an expanded hardscape plan. An existing patio or walkway can be expanded to add shape, size and interest. Ground adjacent to the patio needs to be prepped as normal with a solid, compacted base.
TIP FROM A PRO – The area adjacent to the concrete slab is likely to settle over time so a combination of a paver patio on top of a concrete slab and a traditional paver installation will eventually become uneven.
Professionals Help Avoid Costly Mistakes
Contact Marvin Martinez at Martin’s Brick Pavers, 608-630-8855 or email us at www.marvinsbrickpavers.com for professional, creative installations and detailed, trusted patio planning with the right paver installation options for homes in Madison WI and throughout Dane County.