For septic tank soakaway design a porosity test or percolation test is carried out to determine the permeability of the sub soil.

The rate of permeability calculated from the porosity test allows the correct size of soakaway to be designed.

The standard porosity test involves an excavation of a minimum of 3 test sites. Each hole is then filled with water and the time for each fill to empty is noted. This average time to empty is used in a British Standard calculation to determine the size of soakaway required.

A porosity test also gives our engineers an opportunity of examining what type of sub soil material is present, i.e. chalk, clay, gravel. Clearly less porous sub soils will need a larger soakaway or may not be suitable at all.

Our experience of many years will allow us to undertake these porosity & percolation tests and provide you with the correct solution for your site. We undertake porosity tests for domestic and commercial applications.

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