Guarantees not worth the paper

At present we are working on a property with a basement affected by a failed cementitious tanking system. The homeowner had a guarantee signed by the contractor that installed the waterproofing, and also the product manufacturer/supplier - great right? Well.. no! The contractor is no longer in business, and when the homeowner phoned the manufacturer, they said 'we don't guarantee workmanship'. Very clever that they knew it was a workmanship issue from a phonecall (without inspecting), but regardless, the homeowner literally has a guarantee not worth the paper it is printed on. So, in opening up and removing the friable tanking, this is part of what we found:

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Note the highlighted area where we have started to remove loose/friable tanking, this revealing paint/whitewash on the brick substrate behind.  Such material should be removed prior to the application of a barrier tanking system, since such methods of waterproofing are reliant on forming a bond between the tanking and substrate on which it is applied.  Quite simply, if the tanking does not 'stick' or adhere to the wall, it will de-bond when water moves through the wall, this resulting in system failure, which is exactly what occurred here.

Hence, it is demonstrative of either cutting corners or ignorance.

So, the product manufacturer, although questionably remiss in their initial response were absolutely correct, and furthermore from our initial investigations prior to works commencing, this was certainly not the only issue present with the tanking installation.

So to summarise, the manufacturer sells products to builders and provides them with guarantee certificates/paperwork to satisfy the homeowner, the builder undertakes the work poorly and then goes bump.  The homeowner is left totally in the lurch.

The lessons here are multiple:

Non-specialist builders may not have the necessary experience or knowledge to install tanking systems correctly.
A company tanking guarantee is only as reliable as the installer is finiancially stable.
Product/manufacturer tanking guarantees often mean very little because manufacturers do not take design responsibility and systems usually fail because they are designed/installed incorrectly.
A fancy looking tanking guarantee certificate may look impressive but may not be worth the paper it is printed on...

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