Natural flagstone is an ideal material for creating landscape floors. It’s attractive and durable and blends well with both formal and informal landscapes. Although flagstone structures are often mortared, they can also be constructed with the sand-set method. Sand-setting flagstones is much faster and easier than setting them with mortar.
There are a variety of flat, thin sedimentary rocks that can be used for this project. Home and garden stores often carry several types of flagstone, but stone supply yards usually have a greater variety. Some varieties of flagstone cost more than others, but there are many affordable options. When you buy the flagstone for your project, select pieces in a variety of sizes from large to small. Arranging the stones for your walkway is similar to putting together a puzzle, and you’ll need to see all the pieces laid out.
The following example demonstrates how to build a straight flagstone walkway with wood edging. If you’d like to build a curved walkway, select another edging material, such as brick or cut stone. Instead of filling gaps between stones with sand, you might want to fill them with topsoil and plant grass or some other ground cover between the stones.
Building a Flagstone Walkway
1. Lay out, excavate, and prepare the base for the walkway. Form edging by installing 2×6 pressure-treated lumber around the perimeter of the pathway. Drive stakes on the outside of the edging, spaced 12″ apart. The tops of the stakes should be below ground level. Drive galvanized screws through the edging and into the stakes.
2. Test-fit the stones over the walkway base, finding an attractive arrangement that limits the number of cuts needed. The gaps between the stones should range between % and 2″ wide. Use a pencil to mark the stones for cutting, then remove the stones and place them beside the walkway in the same arrangement. Score along the marked lines with a circular saw and masonry blade set to Vs” blade depth. Set a piece of wood under the stone, just inside the scored line. Use a masonry chisel and maul to strike along the scored line until the stone breaks.
3. Lay overlapping strips of landscape fabric over the walkway base and spread a 2″- layer of sand over it. Make a screed board from a short 2×6, notched to fit inside the edging. Pull the screed from one end of the walkway to the other, adding sand as needed to create a level base.
4. Beginning at one corner of the walkway, lay the flagstones onto the sand base. Repeat the arrangement you created in step 2, with % – to 2″- wide gaps between stones. If necessary, add or remove sand to level the stones, then set them by tapping them with a rubber mallet or a length of 2×4.
5. Fill the gaps between the stones with sand. (Use topsoil if you’re going to plant grass or ground cover between the stones.) Pack sand into the gaps, then spray the entire walkway with water to help settle the sand. Repeat until the gaps are completely filled and tightly packed with sand.