What will you need to get started?

• MOT Type 1
• Builders Sand
• Ballast
• Cement
• Timber for the frame
• Nails or screws
• Shovel
• Rake
• Wheelbarrow
• Level
• Concrete mixer (optional)

SO lets get started, if you want to skip ahead and use the aggregates calculator in step 4 then you will know how much aggregate material you will need to purchase before you start your project.

Building a wooden shed base with concrete ensures a strong, durable foundation that can withstand various weather conditions and provide a stable platform for your shed. This quick guide will walk you through the steps to create a concrete base for your wooden shed, ensuring a professional and long-lasting result.

1. Prepare the Ground

First, choose a suitable location for your shed. Clear the area of any vegetation, rocks, or debris. Mark the area where the base will be constructed, ensuring it is slightly larger than the shed itself.  Let us base this example on a 6ft x 4ft shed, we would allow 4″ all the way around plus the depth of your wooden shuttering which is usually 1″ so the total length and width would be 6ft 10″ x 4ft 10″

2. Create the Framework

Using the timber, construct a rectangular frame that matches the dimensions of your shed plus the 4″ all the way around so 6ft 8″ x 4ft 8′. Secure the corners with nails or screws. Place the frame on the ground where the base will be laid.

3. Excavate the Area

Excavate the marked area to a depth of approximately 150mm (6 inches). Ensure the bottom is level and smooth, using a rake and a level for accuracy.

4. Add the Sub-Base

Fill the excavated area with MOT Type 1 to a depth of about 75mm (3 inches). Compact the material thoroughly using a tamper or plate compactor to create a solid sub-baser dimension of shed.

You can use this calculator to get an estimated amount of aggregates you will need for your shed.

5. Prepare the Concrete Mix

Mix the ballast, builders sand, and cement in a ratio of 3:2:1 respectively. Add water gradually to achieve a workable consistency. A concrete mixer can be used to ensure a thorough mix.

If you are building a shed larger than 4ft x 6ft then you may want to reinforce the concrete, this is something we done ourselves with a 16ft x 10ft shed we build a few years ago and we also build the foundation and deep enough so in the future if we wanted to rebuild the shed in brick we could without having to replace the base. 

6. Pour the Concrete

Pour the prepared concrete into the excavated area, spreading it evenly within the timber frame. Use a shovel and rake to distribute the concrete, ensuring it fills all corners and edges.

7. Level the Concrete

Level the concrete surface using a straight edge or a screed board, moving it back and forth across the frame. Check for any low spots and add more concrete if necessary. Ensure the surface is smooth and level.

8. Allow the Concrete to Set

Allow the concrete to cure for at least 48 hours. Protect it from rain and extreme temperatures during this period to ensure proper setting.

9. Remove the Framework

Once the concrete has set, carefully remove the timber frame. Your concrete base is now ready for the wooden shed construction.

Building a wooden shed base with concrete ensures a strong and durable foundation that can support your shed for years to come. By following these steps and using high-quality materials like MOT Type 1, builders sand, and ballast, you can achieve a professional and reliable shed base.

To purchase any of the materials in this guide, check out our Shop