# Complete Shed Slab Guide Gold Coast | Concreters Gold Coast > Planning a shed slab on the Gold Coast? This guide covers sizing, thickness, reinforcement, drainage, and local council requirements you need to know. [Home](/) [Blog](/blog/) The Complete Guide to Shed Slabs on the Gold Coast Guides # The Complete Guide to Shed Slabs on the Gold Coast Everything you need to know about pouring a shed slab on the Gold Coast, including sizing, thickness, reinforcement, drainage, and council requirements. Daniel Mercer 22 December 2025 · shed slab ## Planning Your Shed Slab on the Gold Coast Building a shed here isn’t just about extra storage; it’s about protecting your gear from our intense sub-tropical climate. You know how quickly a summer storm rolls in over the hinterland and dumps inches of rain in minutes. We have seen plenty of standard [concrete slabs](/concrete-slabs/) crack or flood because they weren’t built for local conditions. The foundation determines if your new structure stays dry during a February downpour or shifts during a dry August. Our team wants to help you get this right the first time so you don’t face expensive [concrete repairs](/concrete-repairs/) later. Let’s look at the specific soil challenges in our region, the regulations you need to know, and the costs involved in 2026. ## Slab Sizing and Thickness ### Standard Shed Sizes Selecting the right footprint is the first step. Homeowners in our region typically opt for these dimensions based on standard residential block sizes: - **Garden shed:** 3m x 3m or 3m x 4.5m (Perfect for mowers and tools) - **Single garage/workshop:** 6m x 6m (Fits a standard vehicle plus bench space) - **Double garage:** 6m x 9m (Accommodates two cars or a boat) - **Large workshop/barn:** 9m x 12m or larger (Ideal for acreage properties in Maudsland or Tallebudgera) ### Recommended Thickness and Strength Most people assume concrete is concrete, but thickness matters immensely. We recommend a **100mm thick slab** as the absolute baseline for garden sheds. If you plan to park a LandCruiser, a caravan, or heavy machinery inside, that 100mm standard is risky. Heavier loads require a thickness of **125mm or 150mm** to prevent cracking under the point load of tires or jacks. This extra concrete creates a “heavy duty” rating capable of handling vehicle weights common in Queensland households. Your slab must also extend **100mm beyond the shed walls** on every side. This extension serves as a vital barrier against vermin and water ingress. ## Site Preparation The Gold Coast has incredibly diverse geology, ranging from pure sand to reactive clay. We approach site preparation differently depending on your postcode. ### Excavation and Levelling A flat pad is non-negotiable. Suburbs like Mudgeeraba, Highland Park, and Pacific Pines are notorious for their slopes. Excavation there often involves significant “cut and fill” to create a level platform. Flatter suburbs closer to the water require less earthmoving but often need better compaction due to sandy soil. ### Compacted Base A stable slab starts with what sits underneath it. Our crews lay a compacted gravel or “crusher dust” base, typically **50mm to 100mm deep**, over the subgrade. This layer acts as a shock absorber. Reactive clay soils, found heavily in Coomera and Pimpama, swell when wet and shrink when dry. The gravel base minimizes the impact of this ground movement on your concrete. ### Vapour Barrier Rising damp is a silent destroyer of shed contents. We install a **0.2mm (200 micron) polyethylene vapour barrier** over the gravel before a single drop of concrete is poured. This plastic sheet stops ground moisture from wicking up into the slab. Without it, you might find your stored tools rusting or cardboard boxes turning to mush, especially in low-lying areas like Carrara or near the canals. ## Reinforcement ### Steel Mesh Options Steel mesh holds the concrete together when the ground shifts. We typically see two main grades used in residential projects. **Comparison of Steel Mesh Grades:** Mesh GradeBar DiameterBest ApplicationCost Impact**SL72**6.75mmGarden sheds, pedestrian traffic, light storage.Standard**SL82**7.6mmWorkshops, garages, vehicle storage, heavy machinery.Moderate Increase Standard sheds often use **SL72**, but upgrading to **SL82** is a smart insurance policy for a small price difference. ### Edge Beams The perimeter of your slab carries the weight of the shed walls and roof. We dig a thickened edge, known as an edge beam, typically **300mm deep and 300mm wide**. This internal “footing” adds immense stiffness to the slab. It creates a rigid ring that helps the entire foundation resist twisting forces during seasonal soil changes. ## Drainage Considerations The Gold Coast averages around **1,200mm of rainfall annually**, but it often arrives in short, intense bursts. You need a plan for where that water goes. ### Surface Fall Water must never pool around your shed. We ensure the slab surface has a fall of roughly **1 to 2 per cent** (10-20mm drop over 1 metre) towards the door or a drain. This subtle slope ensures that if you hose out the shed, or if rain blows in, it flows right back out. ### Perimeter Drainage Water sitting against the edge of a slab softens the soil and causes sinking. Homeowners should install a gravel drainage strip or an agricultural (ag) pipe system around the base. This is critical on flat blocks in suburbs like Robina where water tends to sit on the surface after a storm. ## Gold Coast Council Requirements Skipping the paperwork is the fastest way to get a fine or a demolition order. We advise checking the **Gold Coast City Plan** and Queensland Development Code (QDC) MP 1.2 before starting. ### When You Need Approval Council rules are specific about size and location. - **Size:** Sheds larger than **10 square metres** usually trigger the need for a building approval. - **Height:** If the overall height exceeds 2.4m, setback rules become stricter. - **Length:** If the structure is longer than 9m along a boundary, you will likely need a relaxation application. ### Building Codes Compliance ensures safety and insurability. All work must adhere to **AS 2870 (Residential Slabs and Footings)**. Your certifier will require a Form 15 (Compliance Certificate for Building Design) and a Form 16 (Inspection Certificate) from the concreter or engineer. ### Flood Overlays Many parts of the coast are mapped as flood zones. We often have to pour slabs at a specific “minimum habitable floor level” in areas like Hope Island or Helensvale. This might mean raising the slab height significantly, which requires extra fill and stronger engineering. ## Cost Expectations (2026 Estimates) Concrete prices have shifted, so it pays to have realistic budget expectations. The following ranges cover materials and labour for a standard site with easy access. **Estimated Slab Costs:** Shed TypeSizeApprox. Cost Range**Small Garden Shed**9m²$1,800 - $2,500**Single Garage**36m²$4,200 - $6,000**Double Garage**54m²$6,500 - $9,000**Large Workshop**108m²$12,000 - $18,000 These figures include the base, vapour barrier, SL72 mesh, and a standard finish. **Factors That Increase Price:** - **[Concrete Pumping](/concrete-pumping/):** If a concrete truck cannot back up to the site (common in battle-axe blocks), a line pump costs an extra $800-$1,200. - **Excavation:** Sloping sites requiring machinery hire add to the bill. - **Rebated Edges:** Creating a step-down for water protection takes more time and skill. ## Tips for a Successful Shed Slab A few insider adjustments can make a huge difference to the final result. ### 1. Request a Rebated Edge We highly recommend asking for a “rebate” or step-down at the perimeter. This design feature prevents wind-driven rain from creeping under the bottom track of your shed walls. ### 2. Install Anchor Bolts Wet Drilling into hardened concrete risks cracking the edge. Have your concreter set the “J-bolts” or anchors into the wet concrete exactly where the shed frame requires them. ### 3. Don’t Ignore Curing Concrete needs time to reach full strength. Keep the slab damp for at least 3-5 days after pouring, especially during our hot September to March period, to prevent hairline cracks. ### 4. Plan for Plumbing [Concrete grinding](/concrete-grinding/) and cutting later is expensive and messy. If you think you might want a sink or a toilet in the workshop one day, lay the pipework before the pour. ### 5. Check the Mesh Height Reinforcing mesh only works if it sits in the top third of the slab. Ensure your concreter uses “bar chairs” to keep the steel elevated rather than just pulling it up with a rake during the pour. A well-planned slab is the silent partner in your shed’s longevity. It provides the stability your structure needs to withstand the Gold Coast climate for decades. ### Tags shed slab concrete slab Gold Coast backyard projects ## Related Articles [Coloured Concrete vs Exposed Aggregate: Which Driveway Finish Is Right for You? Compare coloured concrete and exposed aggregate driveways side by side. Learn the pros, cons, costs, and best applications for Gold Coast homes. 20 January 2026](/blog/coloured-concrete-vs-exposed-aggregate-driveways/) [How Much Does a Concrete Slab Cost on the Gold Coast? Detailed pricing guide for concrete slabs on the Gold Coast, covering house slabs, shed slabs, garage slabs, and the factors that influence your final cost. 8 December 2025](/blog/how-much-does-a-concrete-slab-cost-gold-coast/) [Concrete Slab Preparation: What to Expect Before the Pour A step-by-step walkthrough of what happens during concrete slab preparation on the Gold Coast, from excavation to reinforcement to the final pour. 24 November 2025](/blog/concrete-slab-preparation-what-to-expect/) ## Need Advice on Your Project? Our team is happy to provide free, no-obligation guidance on your concreting project. Get in touch today. [Get a Free Quote](/contact/) [Call 0485 012 049](tel:0485012049)