Bureaucratic decisions and political lobbying led directly to the $23 billion headache, says Kevin Clarke

The leaky building epidemic did not happen by accident. It was primarily caused by government mismanagement over more than a decade.

Two government-funded agencies - the Building Industry Authority (BIA) and the Building Research Association of NZ (BRANZ), approved and endorsed new low-cost forms of monolithic cladding that had no chance of working in New Zealand.

Both also endorsed and approved the replacement of traditional flashings with sealant. That had no realistic chance of working either.

Then, having approved such sure-to-fail methodologies, BIA and BRANZ endorsed the idea of fixing porous cladding to untreated timber framing.

Increased thermal insulation requirements restricted air movement in substrate framing, which exaggerated the problem. Thereupon, new and inherently problematic construction methodologies delivered catastrophic results.

Buildings were designed by design professionals who, at the time, were permitted to provide assurance of weathertight construction not by detailing it to be so, but rather, by specifying the result was to be weathertight.

That saved a great deal of design time, and allowed fees to be screwed down to less than one third the cost of designing buildings adequately.

Those who read the designers' specifications were oftentimes not familiar with the technical preconditions for weathertight construction, as a consequence of government's abandonment and denigration of apprenticeships.

During construction, the government permitted developers to make more cost savings, by omitting design professionals from their traditional site observation and authorisation roles.

Instead, the built results were inspected by local government officers, few of whom had the knowledge or training to determine what constituted weatherproof construction and even fewer of whom were even expected to look at weathertightness issues, prior to certifying approval of the faulty construction they inspected.

Along the way, major building industrialists applied their significant financial and political leverage to having their attractively-priced monolithic claddings and untreated timber framing duly approved by the appropriate building industry authorities.

Those approvals were forthcoming, but should never have been.

The size of the problem has recently been stated as $23 billion. That figure is well short of the mark because it presupposes the problem has just started. It hasn't.

Building professionals, who had previously conducted their practices and businesses for decades without fault, suddenly had disturbingly long lists of litigated leaky building claims for which they have been paying, for 10 years or more.

Those litigated costs have already amounted to billions and have forced many companies into liquidation and many people into bankruptcy.

Many lives have been ruined or badly damaged. Insurers no longer offer cover for leaky buildings, so that pot has been burnt.

For all of that time, the primary culprits (who also happen to be the primary financial beneficiaries of the problematic building boom) - namely government, major building system suppliers and property developers; have used their financial resources to buy legal stances that have kept the wolves well clear of their larders.

To give some perspective to the problem, the minister lumbered with this problem has stated that the fix-cost equates to the combined health and education budgets. Impressively large. Or is it ?

For those who have not joined the dots, the total quoted $23 billion cost equals the health and education budgets for just one year . However, costs for the leaky building disaster are spread over 20 years. Not so scary after all.

Those unfamiliar with the problem may not be too concerned about the unaccounted billions that have already been paid by parties that were not the real culprits.

The problem those people faced, was they placed reliance upon government regulations and government-funded building science, both of which fell well short of the mark.

They should have been entitled to rely upon the country's primary building authorities but in doing so it cost them dearly.

Without any doubt, the leaky building disaster is the direct result of a series of government bungles. If logic and equity were to count for anything, the government should pay for its causative role in the disaster.

However, government costs are taxpayers' costs, so we taxpayers would then have to pay. But then, that's how we always solve government bungles.

There are, of course, contributory costs that should be paid by other parties and it's high time the big culprits other than government and local government were held to account. We would be better off without them in the building industry anyway.

There was never any need for this disaster. The faulty building methodologies, faulty regulations, faulty building science, faulty local government practices and government's abandonment of apprenticeships were all too obvious throughout.

Those faulty practices flew in the face of proven and well-understood building methodologies that were known to have worked for centuries.

Apart from anything else, Canada had already suffered exactly the same leaky building disaster, for the same reasons, in the 1980s. Some building professionals, including me, had put New Zealand's building authorities on notice of this fact at the time and requested they address the impending disaster before it happened. Lamentably, they knew better.

Worse, they approved and authorised precisely the same building systems that were known to have caused Canada's disaster.

Of course we must accept new, cost effective building methodologies - but not before they have been properly evaluated, tested and proven to function properly by means of reliable building science and equally reliable building regulation and management.

* Kevin Clarke is an Auckland architect, who also acts as an expert adviser regarding leaky buildings and other litigated issues.