The BGS Ringwood district memoir maps Avon floodplain and terrace deposits alongside variable Palaeogene sands, clays and gravelly plateaux. A garden close to the river should not be assumed to match higher ground around Poulner or previous infill elsewhere in town.
Drainage, old foundations, imported soil and tree cover further affect the near surface. We use local evidence to inform questions while keeping the recommendation specific to the room and footprint.
There is no requirement to provide a ground report before contacting your local JustBases team. Start with what you want to build and what you know about the garden.