Extending Your Concrete Patio with Pavers
Most newer homes are sold with an open concrete patio out back, usually only big enough for a small grill, a couple of chairs, and a plant or two. Homeowners who are serious about using their outdoor living area find a small slab patio is just too little for entertaining or any real kind of enjoyment.
The solution: extend the patio. Pouring additional concrete can get expensive as permits are required in many areas to pour concrete and that usually involves hiring a contractor, driving the cost of this project into the thousands. An alternative to pouring more concrete is extending the patio using pavers.
Patio pavers offer homeowners many benefits. They are easy to install so homeowners can make the extension of a concrete patio a weekend do-it-yourself project. Pavers come in a large variety of shapes, sizes, colors and materials giving homeowners flexibility in creating additional outdoor living space. Pavers can be used to create large or small spaces as well as making that space as formal or informal as the homeowner wishes. They are also easy and inexpensive to repair.
With proper preparation and planning, the DIY paver project becomes easier. Planning is the key. Use graph paper to draw to scale the existing patio, home, and any landscaping that will not be removed. The drawing helps with the preparation and material ordering.
The number of pavers needed for the project can be figured easily for a regular-shaped project, such as square or rectangular. Use the square footage of the new patio space plus 5% for cuts at the edges. Irregularly-shaped patios will require more cuts so an extra 10% for that material should be purchased.
Outline the area where the patio will be. Use string or a garden hose for the outline and stakes to keep the string or hose in place. When laying out the outline, take into account that guards will be used to keep the base and pavers in place and the base should extend beyond the guards roughly the width of the paver, usually 4” to 6”.
One of the most important parts of preparing for the pavers is preparing the slope. All patios should slope away from the house, or in this case away from the existing patio, for proper drainage and to prevent rain from standing in low places on the patio. The slope should be at least 1/8” over one foot so if the patio is 8’ long, the slope should
be 1” from the back (edge by the existing patio) to the front. Many paver installers recommend a slope of ¼” for the best drainage.
In most cases, excavating will include removing sod or grass. A sod remover or sod cutter can be rented to make this process easier. The amount to be excavated below the grass will depend on the height of the pavers and whether the soil is very wet. The base is typically 5” plus 1.5” for the sand layer plus the height of the pavers. In very wet soils, the base layer should be up to 12” plus 1.5” for the sand and the height of the pavers.
After excavating, strings can be run from stakes at the existing patio to the front of the new patio area and adjusted to show the slope needed. Running strings crossways as well will ensure the pavers are level across the entire patio.
Installing a Paver Patio
Lay the Base
The base is usually made up of a crushed rock material. It should be laid no more than 2” at a time and then compacted. For a small area, a hand tamper can be used to compact the material, but for larger areas use a plate compactor which can be rented for the project. Compacting the base layer ensures good stability under the pavers. Laying it only 2” at a time ensures that the entire base is compacted properly. The base layer can be watered to help the compacting. Continue adding and compacting base material until the right height for the base has been reached. Be sure to lay the base outside the patio area to ensure the pavers at the edges are stable.
Edge restraints help hold the pavers in place. They are usually wood, metal or plastic and are installed around the edge of the project with 12” spikes. For irregular shaped patios, the edging may have to be cut to contour to the curves in the project.
The Sand Layer
The sand in a paver patio acts like glue. Use a coarse sand and screed it smooth to the desired height, no more than 1.5” thick. A small project can be screeded with a 2”x4” but for large projects the sand should be laid and screeded in 50 to 100 square foot sections, finishing one section before moving on to the next. Aluminum pipes can be laid down to measure out the sections then lifted off as needed and the groove left behind filled in and screeded.
The project is almost finished when it’s time to lay the pavers. After all the hard work of prepping and laying the base, laying the pavers is easy. Begin laying them at a 90 degree corner, preferably adjacent to the existing patio. Work from the existing patio out, laying the pavers in straight lines in the sand. They should be laid directly into the sand where they will sit, not slid into place as this will displace the sand beneath, and should be 1/8” apart. Stand on the pavers already laid to continue the work, rather than on the sand. From time to time, check that the pavers are straight and levels using a string as a measure.
Lay all of the whole pavers first then come back to make the necessary cuts at the edges. Pavers can be cut using a masonry saw. Be sure to use safety goggles and follow all of the manufacturer’s safety guidelines.
After all the pavers are laid, use the plate compactor to tamp the pavers into the sand. Finish the project by sweeping a fine sand into the joints between pavers. This will lock the pavers into place. Sand will probably need to be swept into the joints a few times as it will settle with use and rain.
To ensure lower maintenance, the pavers can be sealed. A sealer will protect the pavers against moisture, keep the sand between the joints in place and help prevent weed growth.
Now that the patio is finished, it’s time to enjoy. Invite over the friends and family, have a barbecue and enjoy the products of a job well done. A paver patio should last 10-20 years and offer lots of enjoyment.