Some advice please – I planning a single skin brick/block garage [building regs approval not required], one side will be <1m from my neighbor's garage and above a disused rubble soak-away [clearly 5m rule didn't exist when that was dug out]. What is the minimum work necessary to achieve sufficiently stable foundations for the new garage? I guess ideally the soak away should be excavated down to underlying stable soil surface and then go from there – however this could be below bottom of neighbor's garage footings – so I'd like to avoid full excavation if possible. Any thoughts would be most welcome.
