Setting stones into concrete can give a plain concrete patio a new look. An added plus to a stone-laid patio area is that the stones are less likely to be slippery when wet, as opposed to regular concrete. Keep in mind that this project will take almost a week. Having the assistance of a friend or family member can certainly make it easier.
How to set stone into concrete
Lay the pieces of lumber around the concrete area where you would like to set the stone. Using a hammer, drive wooden or metal stakes into the ground at equal intervals (about 12 inches) on the outside of the lumber to hold the lumber steady. Using a hammer and nails, connect the ends of the adjoining pieces of lumber to keep them from slipping away from one another.
Get a load of stones that are close to the same thickness. The thickest stone will be the one to set into the concrete first, as it will determine the thickness of the layer of concrete for the following stones.
To prepare your concrete mixture, you will need a bucket. Mix three parts of sand to one part of concrete. Add water until the mixture is rather thick. You will need to be able to pour it out of the bucket while working with one stone at a time, but it also needs to be thin enough for you to press your stones down into it. Prepare small batches so that the mixture does not harden before you get to use it.
Choosing a beginning point to start laying your stones (it should be near the edge of your concrete area), lay the stones one by one. Outline the concrete area with stones, tapping each one lightly once or twice to ensure that it is embedded in the concrete mixture. To do this, pour a small amount of concrete mixture where you plan to lay the stone, and then set it carefully. The top of the stones should be about 1/4-inch lower than the top of the lumber barrier.
Continue to the next stone. Pouring another small amount of the concrete mixture, set the stone and tap it, leaving a gap of about 1/4-inch between the two stones. If any concrete mixture oozes up between the stones, wipe it away with an old rag. Work stone by stone until the entire outside edge of your concrete area is completed.
Allow the stones along the edge to sit for 24 to 48 hours, so that the concrete mixture can become very hard.
Once the border stones are properly set, fill in the middle of the area, working from one side to the other, so that you don't find yourself stuck in the center. Remember to use a small amount of the concrete mixture at a time and leave a 1/4-inch gap between each stone. Any concrete mixture that comes up between the stones should be cleaned away with an old rag.
Once all of the internal stones are laid, allow them to set for 24 to 48 hours, so that the concrete mixture can become very firm.
Prepare your grout mixture in your second bucket. Combine one part of sand to one part of concrete with enough water to make it flow easily.
To prepare your grout bag for use, trim about 1/8-inch off the tip of the bag, using your scissors. This will enable the prepared grout to flow from the bag into the space between the stones.
Fill the grout bag about 3/4 full of the grout mixture, and then twist the top of the bag so that the grout does not come back out of the top when you are squeezing the bag.
Beginning at one side of your area, gently squeeze the grout bag while holding it over the 1/4-inch gaps in between the stones, allowing the grout to flow into and fill the space. Wipe away any excess grout with an old rag before it begins to harden.
Allow the grout between the stones to cure for 24 to 48 hours before walking on the stones. Rinse the area off with a water hose to remove any debris after three days.