SIGMA GPS Drainage Sheet (£-POA)

Primarily used for external tanking applications, forming a high compressive strength void, providing a path of least resistance for water, which enables controlled drainage into outlets or connector pies. Its can be used in combination with GP gas/waterproofing barriers to provide both protection and drainage for external tanking application, ensuring gas/waterproofing barrier remains intact and the system performs as intended.

SIGMA GPS Drainage Sheet should be installed with the geotextile facing the soil/backfill, and the direction of water flow. Rolls can be cut to size on site. It can be held in place prior to backfilling with DS Butyl tape (50 mm wide), or mechanically fixed in the absence of a gas/waterproofing barrier.

Adjacent rolls can be overlapped using the geotextile, secured with DS Butyl tape (50mm). Roll ends can be connected by simply butting the cuspate sheet together.

Connection to land drains/collection pipes is achieved by placement within the slotted areas, or removal of the cuspated core and wrapping of geotextile around the pie. Care must be taken not to damage/cut the geotextile during core removal to facilitate the connection.

Backfilling should proceed with caution to avoid undue stress on the sheet. Compactive effort should be avoided within the first 100mm of the sheet.

Roll weights can be up to 35kg and hence appropriate equipment is required for unloading and handling. SIGMA GPS Drainage Sheet is supplied in packaging designed to protect the product from damage during handling and storage, and degradation as a result of UV exposure. SIGMA GPS Drainage Sheet should be kept in the supplied packaging until such time as it is required for installation, and then covered within 2 weeks of installation.

• BBA Certificate 20/5728
• CE
• UKCA
• UKNI

NBS Specification Sheet

Technical Data Sheet