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generalBagged Brick WallShuttered Concrete Wall

Retaining Walls General

Derbigum CG membranes together with a hydrostatic pressure relief system are generally used on shuttered concrete walls and bagged brick walls where wet conditions are anticipated.


Ensure adequate and dry access for the waterproofing installation. De-watering may be necessary depending upon the water table.


Internal angles are to be rounded with a minimum 35mm radius mortar cove so as to ensure continuous adhesion through the corner and prevent rupturing or delaminating during backfill and compaction operations. External angles are to be smooth and rounded.


So as to prevent a build-up of water on the external side of the wall, the ground water should be taken away through either a drainage medium against the waterproofing, which allows the water to reach sub-soil drainage, or an agricultural drainage system to falls around the structure, or into the sub-floor drain system.
Irrespective of the system used, a selected sand layer should be utilized to prevent the geotextile filter from clogging.


Derbigum waterproofing membranes must be protected from damage during the back fill operation to prevent rubble, (bricks or other debris) from damaging the membrane particularly during compaction. This protection may be a brick skin, polystyrene, fibrecement or softboard (or a combination of these). Alternatively a HD polyethylene Delta drainage layer may be used which serves the dual purpose of both protection and drainage.


The top edge is to be terminated a minimum of 100mm above anticipated ground level and is to be secured and protected.

The membrane is to be terminated a minimum of 100mm over the edge of the footing - see detail.

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