A base has three jobs: keep the building level, carry it without movement and separate vulnerable timber from persistent moisture. The best method depends on the ground, access, drainage, building weight and the maker's support layout.
Start with the installation drawing
Find the exact floor footprint and bearer positions before choosing a method. A maximum roof dimension is not a base plan. Use the base calculator to keep the agreed finished dimensions in one place.
Compare the approaches
Concrete can provide a continuous, durable surface but needs careful levels and drainage. Paving can work well on a properly prepared sub-base. Timber frames and proprietary systems can reduce wet work and suit some sites, but their support spacing must match the building.
No method rescues soft, poorly prepared ground. Ask who is responsible for excavation, sub-base, finished level, squareness and drainage before installation day.
Leave water somewhere to go
Avoid creating a lip that holds rain against the floor. Keep soil and planting away from the walls, and plan gutter discharge before the first storm rather than after it.
This guide will be expanded with verified construction diagrams and a hand-off to the Plankley material calculators.