MARRICKVILLE, NSW

The homeowners wanted to convert the existing sandstone wall basement into a dedicated wine cellar and laundry. A sandstone substrate meant that other negative side systems were not suitable to make this area waterproof. A cavity drain system was specified as the ideal solution. 

Project Description

This property was built over 100 years ago with what is referred to as a ‘walk-out basement’ on a sloping block. The original basement had been constructed of sandstone block which the owner wanted to ‘push back’ or extend to create a larger space to convert into a laundry and wine cellar which required the area to be free of both active water ingress, plus moisture and condensation.  

External access was not a viable solution, requiring an internal negative side membrane be installed. The solution had to accommodate for the sandstone and concrete construction meaning that liquid negative membranes would not be suitable due to lack of adhesion and the inability to prepare the surface correctly. A negative hydrostatic liquid membrane would have transferred any groundwater to other areas of the basement. 

Finding and alternative solution to optimise space was also a high priority as building additional walls to create a ‘cavity’ would have encroached on the area which was unacceptable to the owners. 

Design Solution

Our in house CSSW (Certificated Surveyor of Structural Waterproofing) designed the ‘Type C’ Cavity Drain system for this project as it would not only mange the active water leaks it would also mitigate any condensation and moisture vapour that could form between the substrate and the intended frame and plaster linings ensuring the area stayed free of any groundwater ingress. 

Prior to waterproofing installation works the basement area was excavated, extended and underpinned with concrete and blockwork. An infill concrete slab with an in-floor drainage and sump pit was also included as part of the new slab design. 

Works required installation of the Newton System 500 membrane to the internal walls with Newton Multiplugs and overtapes, and installation of the Newton Basedrain to the perimeter spoon drain rebates. 

Reinstatement works were completed by the Home-owner’s Builder to create a 100% dry, habitable area giving the client the extra space they needed with complete peace of mind.