How To Prepare Your Site For A Shed
Get a Quote
Knowing how to prepare your site for a shed is what separates a build that stays solid for decades from one that shifts or cracks within a few years. Get the groundwork right, and the rest of the build goes to plan. Rush it, and you'll be paying to fix problems once the steel is already up. Here's how to get your shed site ready.
Before you start: check local building regulations and choose your shed's location
Putting up a shed on your land is not simply a matter of choosing an area that suits you. There are legal considerations as well as practical ones that must be taken into account before this step can be taken. It is necessary to be aware of the building codes applicable in your state or territory, as well as your local zoning by-laws, before proceeding.
One of the initial stages involves verifying the necessary setbacks. This refers to the minimal distances between the construction and your land’s boundary, which are set by councils. Depending on where you reside, there can be vast differences in the measurements required. Contacting the council will help you get all the information. If you're planning to build near the edge of your block, our guide on whether you can build a shed on the boundary line runs through how setbacks work.
Ensure you examine your property title for any easements. These are specific portions of land designated for utilities such as drainage or sewer pipes. Building on an easement can lead to costly removals in the future if access is needed. We explain what to look for in our guide on building a shed over an easement.
Once you understand the rules, choose a suitable spot for construction. Selecting a flat area reduces the need for extensive earthwork. Opt for a location with good drainage that is close to your driveway. This choice will help you save both money and effort when the shed is delivered.
Clear the shed site of vegetation, debris and organic material
At this point, you want the ground to be clear and stable, free of anything that might decay or move. Start by removing grass, weeds, roots, and any organic material on or just beneath the surface. Organic matter decomposes over time, creating soft spots that can lead to uneven sinking under pressure.
Also, clear away loose rocks and debris of all sizes that could obstruct progress. If there are any existing structures in the area, dismantle those as well. You can either dispose of the excess soil or use it to elevate a low area of the site, as long as it's packed down firmly.
Level the ground to create a flat, stable surface
To ensure a sturdy foundation, the pad must be perfectly level from one corner to the other. Simply estimating by sight won't suffice. A steel frame needs to be square, and any unevenness in the base can lead to doors sticking and undue stress on the structure over time. To achieve this, you should cut into the higher side and build up the lower side until everything is even.
Equally important is the compaction of the soil. Loose fill must be packed down in layers using a compactor. If the soil isn't properly compacted, it will continue to settle under the weight of the shed, causing potential issues later on. A well-prepared site should feel firm underfoot, with no soft or bouncy areas. This solid base helps ensure the longevity and stability of the structure.
Sort out drainage so water drains away from the shed
Ensure the pad directs water away, rather than letting it accumulate, by sloping the surface downwards from all sides of the shed. Stagnant water can lead to long-term issues, like a damp floor or the rusting of steel where it contacts the ground. Even robust Australian steel benefits from being on a dry pad.
For effective drainage, aim for a gentle slope, with a drop of about 50 millimetres over the first few metres. Avoid placing the shed at the yard's lowest point, where water tends to gather after heavy rain. If your property experiences significant runoff, consider installing a simple drain or a gravel trench around the pad. This setup helps channel water away from the foundation, keeping it dry and stable.
Choose the right foundation for your shed
Different situations need different foundations; hence, the type of foundation you will need will depend on your soil type and the shed you will construct. A larger metal shed will require a stronger foundation than a smaller storage shed. You can browse our residential sheds to get a sense of the sizes on offer.
Concrete slab foundation
When it comes to building a steel shed, a concrete slab is often the top choice for a foundation. This preference isn't without merit. A concrete slab provides a stable, level surface and offers secure anchor points to withstand strong winds. It also ensures a clean and dry floor for your shed. For both residential and commercial projects, a concrete slab is usually the go-to option.
Typically, a standard slab is designed to be thick enough to support the weight of the shed and is reinforced with steel mesh. In cases where the shed needs to accommodate vehicles or heavy machinery, a thicker slab is poured to prevent any cracking. If you already have a slab on your block and want to know whether it'll do the job, our guide on building a garage on an existing concrete slab is worth a look.
Concrete piers
Concrete piers offer an ideal solution for building on sloped terrains or in areas where laying a full concrete slab would require extensive digging. Workers dig holes deep enough to reach solid soil, fill them with concrete, and then place the shed frame on these piers. This method ensures the shed remains level, regardless of uneven ground above.
Using piers minimises the need for extensive excavation on steep sites, which can significantly reduce both time and expenses compared to levelling the ground for a slab. They provide a reliable foundation, especially on challenging terrain where constructing a slab would be difficult.
Gravel base
If you're looking for an affordable way to keep moisture away from stored items, a gravel base is a solid choice. Its natural drainage properties make it ideal for smaller storage needs. When you compact the road base and secure it with timber or steel edging, you create a stable, level surface perfect for a small storage shed.
However, gravel isn't suitable for every project. It lacks the tie-down strength of concrete, making it less suitable for larger structures or spaces where you plan to park vehicles or work regularly. Consider your specific needs before deciding on this option.
Let the ground settle before construction begins
When you've just finished levelling a site with excavated or fill soil, the ground isn't ready to support construction immediately. This freshly disturbed earth contains air pockets and hasn't yet settled into a stable position. Rushing to build can lead to cracked concrete slabs and other structural problems later on.
It's wise to wait about three weeks for the soil to settle and firm up. A few rounds of rain and some compaction can help speed up this process. Ignoring this waiting period might seem harmless at first, but it can cause significant issues down the road. Remember to incorporate this settling time into your overall project schedule, too.
Clear a path for delivery and leave enough working space
It's easy to forget about access until delivery day arrives, so ensure the path to the pad can accommodate a loaded truck and the crew. A site might be perfectly prepared, but it's useless if the truck can't reach it. Double-check that gates and driveways are wide enough, and make sure the ground is firm to support a loaded vehicle without getting stuck.
Also, leave enough space around the pad for the crew to work comfortably. Ideally, provide a few metres on each side for moving materials and assembling the frame safely. Be mindful of overhead obstacles like tree branches and power lines, which can interfere with crane or truck operations. If you're building near power lines, refer to our guide for important considerations.
Frequently asked questions
Constructing a shed on grass or soil is not ideal, as the ground is uneven and the material beneath decomposes and shifts around. A shed requires a proper foundation to be constructed to ensure that it is levelled. Bare soil will also retain moisture, which can result in corrosion of the metal parts of the shed.
The typical concrete slab size for a shed is usually 100mm for general usage purposes. However, if you need your shed for parking vehicles and operating machinery in a workshop setting, then a minimum thickness of 150mm is required for such a purpose. The ideal size ultimately depends on the intended function of the shed and soil conditions.
For sites with slopes or soft soils, concrete piers make an ideal choice for construction, as they extend beyond the surface into more solid soil beneath the surface. They also handle reactive soil well. This is the type of clay that expands upon becoming wet and shrinks upon drying up, and this process could crack the slab over time. A slight slope would accommodate a slab with a little bit of excavation. Our guide on building a shed on sloped ground goes into the detail if your block isn't flat.
In Australia, most sheds require some kind of council approval, although this varies according to your particular state or territory and local council. There are some sheds that are classed as exempt development, which means that no approval is needed, while other sheds require some kind of permission. You should contact your local council before you begin to make sure that you have all the necessary permissions.
If the surface is relatively flat and you feel confident about operating rental equipment such as a compactor, then you can create the shed foundation yourself. However, if there is a slope involved or if you have to pour a concrete slab, it’s best to leave it to professional contractors who will do it properly. A professional electrician should always be hired to wire your shed.
Try to leave at least 500 millimetres of clearance from the shed when it is complete, but be sure to find out your local authority’s requirements for building setbacks first. The space will allow you access to the roof for gutter cleaning and wall maintenance, as well as preventing plants growing against the steel. Leaving room on all sides also stops water and debris building up against the base.
