In these cases, very low porosity is desirable and can often be achieved.
Substrate with low porosity that permits limited transmission of groundwater is known as an aquitard.
The material produced in this process has a very low porosity of about 3%.
By this process the tiles created have very low porosity.
Thus creating a single mass making them extremely hard with low porosity.
This data also suggested that extraction would be limited due to a low porosity and permeability.
Slate or "engineering bricks" with a low porosity were often used for the first few courses above ground level, and these can help minimise the problem.
This seems counterintuitive because clay soils are termed heavy, implying lower porosity.
Normally greaseproof paper is produced by refining the paper stock and thus create a sheet with very low porosity.
It was also found that a silicon wafer with medium to low porosity displayed more stability.