Checking with your local building department is a good place to start. If you know a local contractor or engineer, they are likely aware of regulations in your area. You can also ask them if there are certain regulations you have to meet.
If you’re planning a 10 feet (3. 0 m) x 10 feet (3. 0 m) shed, measure out these dimensions and mark them in the ground. Plan on starting your stem wall on this perimeter.
For example, if you’re building a rectangle structure and your wall will be 6 feet (1. 8 m) long, 1 foot (0. 30 m) thick, and 4 feet (1. 2 m) high, you need 96 cubic feet (2. 7 m3) of material for that section. Then multiply that by 4 to get 384 cubic feet (10. 9 m3) for the whole wall. Use a different formula if you are calculating the volume of a circular structure. If a pack of bricks has a volume of 20 cubic feet (0. 57 m3) and the total volume for your wall is 384 cubic feet (10. 9 m3), then you need 20 packs of bricks. If you’re having the stones delivered, ask the drivers to place the stones as close to your building site as possible so you don’t have to carry them long distances.
Make the bottom of this trench as level as possible. If you encounter any stones or obstructions, remove them to they don’t get in the way of your wall.
Then, lay out landscaping fabric so it covers the gravel and both sides of the trench. Leave some fabric remaining at the top so you can wrap the fabric around the top of the drainage system. Finally, pour gravel into the trench until it fills 1/3 of the way to the top. You can buy bags of drain-grade gravel at a local hardware or garden supply store.
If you plan on connecting your drainage pipe to a local storm drain or sewer, make sure you receive permission from the local government. If you have water on your property, you can extend the drainage ditch so it empties here.
If the wall is more than 1 stone thick, lay more stones parallel to the first ones. Act as if each section represents one stone.
The interlocking stone structure should look like a zipper going up. Stack 3 to 5 layers of stones at the corner before filling in the rest of the wall. Then if you need to go higher, stack more layers at the corners.
Make sure each rock you place is secure. Push it down to lock it in place snugly. Pound them down gently with a rubber mallet if you have to. Always stack a complete layer around the whole perimeter before starting another layer.
If your bricks are smaller and you need to use more than one to cover the width of the trench, make sure the stones nearby touch each other. Otherwise, the wall won’t be able to support much weight. [13] X Research source
Do not build the stem wall higher than 8 feet (2. 4 m). A wall higher than this requires extra reinforcement. Many localities even ban stem walls higher than 4 feet (1. 2 m) for safety reasons. [15] X Research source
Check the wall in multiple locations to confirm that it’s level across its whole perimeter.
Pouring this much cement is a big job. Consider contacting a contractor to do this step for you. You can also build a foundation with large rocks or bricks. This is only for a smaller structure.
