Shed and equipment pads are usually reinforced slabs over a compacted gravel base, while workshops and garages need thicker slabs and footings. Foundations for additions must meet the locally adopted building code, typically with permits, inspections and sometimes engineered drawings, and may require a licensed contractor depending on scope. Call 811 before digging.
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Sheds, workshops, detached garages, carports, hot tubs and home additions all need something solid to sit on. For smaller structures, that's often a simple slab. For anything attached to the house or built for living space, it usually means engineered footings and foundation work that must meet the building code and pass inspection.
Common slab and foundation projects
- Pads for storage sheds, playhouses and garden buildings
- Slabs for workshops, detached garages and carports
- Pads for hot tubs, generators and HVAC equipment
- Footings and slabs for room additions, sunrooms and screened porches
Small structures and pads
A shed or equipment pad is usually a reinforced slab over a compacted gravel base, sometimes with a thickened edge around the perimeter. Size the pad to the building plus a little extra, make sure it's level for the structure but still sheds water at the edges, and confirm the location meets setbacks from property lines, easements and septic fields. Many Metro Atlanta cities and counties require permits for accessory buildings above a certain size, and HOAs often have their own rules, so check before you pour.
Workshops and garages
A slab that will hold vehicles, heavy tools or equipment generally needs more thickness and reinforcement than a shed pad, plus thickened edges or footings to carry the walls. If you plan to heat or finish the space, ask about a vapor retarder under the slab, insulation and where plumbing or electrical conduit should be placed before the pour.
Additions and structural work
Foundations for additions and other habitable spaces carry the weight of the structure and must follow the residential building code adopted by your local government. That typically means a permit, footings sized for the soil and load, inspections before concrete is placed, and sometimes engineered drawings. Georgia licenses residential and general contractors through the Secretary of State, and work on additions and other structural projects may need to be performed or overseen by a licensed contractor depending on scope. Concrete subcontractors commonly pour these foundations under a general contractor or builder who holds the permit, so make sure everyone's role is clear.
Georgia soil and site factors
- Clay and fill: footings should bear on firm, undisturbed soil. Loose fill or very soft clay may need to be removed or the design adjusted.
- Frost depth: Atlanta's frost depth is shallow compared to northern states, but footings still need to extend to the depth your local code requires.
- Drainage: keep the slab elevated above surrounding grade and slope the ground away so water doesn't collect against the new structure.
- Utilities: Georgia law requires calling 811 to have underground utilities marked before digging.
Questions to ask
- Does this project need a permit, and who will pull it?
- How thick is the slab, and what reinforcement and base are included?
- Do you need engineered drawings, and are inspections scheduled before the pour?
- What do you need from the shed, garage or addition builder before you start?
Planning a building or addition? Request a slab or foundation contractor and include the structure's size and use.
Frequently asked questions
Do I need a permit for a shed slab in Metro Atlanta?
Many cities and counties require permits for accessory buildings above a certain size, and some for the slab itself. Setbacks and HOA rules also apply. Check with your local building department before pouring.
Does a concrete contractor need a license in Georgia?
Georgia doesn't generally require a state license for concrete flatwork like driveways and patios. Residential and general contractors are licensed by the state, and structural work such as foundations for additions may need a licensed contractor depending on scope. Check with the Georgia Secretary of State's licensing board.
How thick should a shed slab be?
Shed pads are commonly about four inches thick over a compacted gravel base, often with thickened edges. Heavier uses, like a workshop or vehicle storage, usually call for more thickness and reinforcement.