A combination of many factors has lead to a legacy of leaking
buildings built from the 1990s to 2004/2005, many of which are still
unidentified. Various problems had been noticed, and their causes
understood early in the process, but significant action was taken only in
2004/2005 when changes were made to the Building Act.
All this did not prevent city councils form issuing Code Compliance
Certificates to builders and developers. Most of them had, after all, followed
the letter of the law, i.e. the then current Building Act, which allowed
certain practices now discontinued. It did not weed out those builders either
whose shoddy workmanship could not be spotted under a seemingly perfect,
smooth external finishing.
A recipe for disaster
lax building regulations which allowed untreated
timber to be used for framing
installation of monolithic cladddings without a
cavity for drainage and ventilation
inappropriate materials for New Zealand's climate
bad designs that made homes more leak-prone
installation techniques that did not follow the
manufacturers' proprietary instructions
cheaper substitute products for any of the layers
applied to create a monolithic finish
bad workmanship owing to a number of reasons,
e.g. lack of experience with new materials and building techniques, or
lack of suitably qualified builders due to a skills shortage