Background: Saint Patrick’s Cathedral was built in 1845 using natural stone. With time the heritage building has experienced weathering and degradation, particularly along the plinth of the building. Ground moisture was identified as the main cause of degradation and weathering of the natural stone structure.
Problem: As part of preservation and restoration work, a drainage trench with gravel was built around the building. However, with time the effectiveness of drainage trench was reduced due to migration of clayey soils into the gravel in the drainage trench.
Solution: To filter and drain groundwater including moisture due to capillary action, DuPont Typar geotextile was selected. Typar SF geotextile unique design allows water to drain without clogging of the gravel. Typar SF has previously been used on other restoration projects in Pakistan and as well as internationally.