All of our generators have a base that supports the generator.   When we install a generator system, we include site preparation as part of the installation.   The purpose of our site preparation is to ensure a solid, level foundation for the generator and also raise the level of the generator above any surface rain water.   For home generators up to 20kW, we use 4×6 Grade 1 treated timbers to frame a level box.   The box is filled with a compacted mix of granite rock and pea gravel.   The rock helps provide a quieter and cleaner installation.   All liquid cooled generators require a concrete slab because of their weight.