Installing a crushed stone shed pad with a 4x4 or 6x6 pressure treated timber border provides a stable, well-draining foundation. A standard pad should be a minimum of 1 foot larger than the shed on all sides to allow for water runoff.
Our process is typically as follows:
1. Site Preparation
- Mark the Perimeter: We use stakes and string to mark an area 2 feet wider and 2 feet longer than the shed's footprint.
- Check for Utilities: Before digging, we always contact your local 811 Utility Service to mark public underground lines and utilities. The homeowner is required to mark any private utilities (dog fence, well line, septic, etc.)
- Excavate: We remove sod and topsoil to a depth of 4-6 inches to expose the subsoils.
2. Install the 4x4 or 6x6 Border
- Level the Base: We install a thin layer of crushed stone where the timbers will sit to help with fine-tuning the level and drainage.
- Assemble the Frame: We lay pressure-treated 4x4 or 6x6 timbers around the perimeter and adjust them to make sure they are level and square.
- Secure the Timbers:
- We fasten the corners together with 12-inch treated screws or landscaping spikes.
- We anchor the frame to the ground by drilling holes through the timbers and driving 1/2-inch rebar stakes (at least 18 inches long) into the soil.
- Some sites with significant elevation differences (slopes) can require additional procedures to create a level surface for the shed. Common remedies often include, bringing in additional fill, cutting into hillside and removing fill, stacking timbers, or a rock retaining wall to correct the elevation differences. These remedies can be discussed during our complimentary site visit.
3. Lining and Filling
- Weed Barrier: We install a geotextile fabric, or a heavy-duty landscape fabric over the bare soil and staple it to the inside of the 4x4 border to prevent weeds and keep gravel from sinking into the dirt.
- Add Crushed Stone: We fill the frame with 3/4-inch clean crushed stone. We avoid smooth river stones or "crusher run" (stone dust), as they do not drain as effectively or provide the structural stability that is required for a proper installation.
- Compact and Level: We spread the stone evenly with a rake. We use a plate compactor or hand tamper to firmly pack the gravel in layers until it is level with the top of the 4x4 or 6x6 border.
4. Finishing up
- Final Landscaping: We spread loam around the pad area abutting the timbers and over any areas that were disturbed during the excavation. The homeowner is responsible to seed these areas once the shed has been installed.