Originally Posted by taras0000

Nope. Use the existing base as a foundationd. Drill into it and secure new re-bar, and lay down a layer over top of the old one. The drilling can be done by unskilled labour, keeping costs down, and the old foundation tied to the new layer will strengthen the whole structure. The only thing preventing this and causing a total rebuild is whether the ground would be able to support the additional weight, and that's just the cost of a geomatics survey, so a couple of thousand dollars.