what is standard guarantee for tanking cavity wall

Hi A standard guarantee is usually between 5 - 10 years depending on the system used. If the work is a complete tanking system, ideally it should comply to BS:8102 and this is usually covered with a 10 year guarantee. If it's just one wall to be "tanked" then a 5 year guarantee is the norm. Technically, the term 'tanking' cannot be used for 1 wall as it does not protect the whole room. When tanking one wall it is very important to ensure the water is not going to be diverted to another wall/floor and this should be addressed at point of inspection.