A missing flashing leaves timber exposed on the roof of this house, allowing water in.

A council building inspector uses a spirit level to show how far out this wall is.

The council laid a complaint with the Licenced Building Practioners Board about this site - 48 truckloads of metal had to be brought in to support the house above.

The lack of supporting foundations under this masonry wall is disturbing, the council says.

This GIB Handibrac has been secured with nails, despite the instructions on how to fit it properly lying nearby.

There is nothing for the bolts of this steel portal frame to be secured into.

The foundation holding up the post of this two-storey house has been hacked away.

Council building inspectors told the developer of this residential site to rip down this substandard masonry block wall and start again.

The steel portal of this two-storey house has been packed with untreated timber to level it.

The steel framing of a two-storey house bolted to nothing and a site which failed 19 out of 27 inspections are the kinds of horror stories Auckland building officials come across every day.

Auckland Council is failing around 30 per cent of inspections as the city experiences an extended building boom.

The substandard work his team comes across is "frustrating", manager building control Ian McCormick said.

At one site the steel framing holding up a house was wider than the foundation it rested on and therefore not bolted to anything.

READ MORE:

* Auckland council faces $27m repair bill to new headquarters

* Shoddy building practices rife in Auckland

* Videos of building horror stories no surprise

At another the framing had been levelled by packing untreated timber under it. "The person who did that was an idiot," McCormick said.

These sorts of errors should be picked up by the Licensed Building Practitioner overseeing the job, but many were working on multiple sites at once, he said.

"There's people out there who think we (the council) provide quality control on the job… In actual fact it's the designer and it's the builder's fault, it's their responsibility."

Council inspectors had the ability to shut down a job and make the developer do remedial work.

At one property where a temporary retaining wall had not been built as required, the council ordered that 48 truckloads of material be brought in to make sure the neighbouring house didn't collapse.

But once the remedial work was done the builder could continue working on the project and potentially fail further inspections.

"Unfortunately we can't just say, 'look you've got no idea what you're doing, just stop and go away'."

Having to do repeated inspections sucked resources, McCormick said.

It was also a concern that council officials would not pick up every detail.

An inspector happened to notice that flashing near the roof of one house was missing, meaning water would get in and damage the timber.

On another project a commonly used GIB Handibrac had been attached with just a few nails, rather than the required screws. The instructions showing how to do it properly were lying nearby.

That one incident in itself would not necessarily cause a problem, McCormick said.

"But a person who does that once is going to do it as often as he feels he needs to."

The horror stories weren't indicative of the quality of builders across the board, and in some instances it could be a case of a competent practitioner getting busy and hiring subcontractors they didn't normally use, he said.

The council was working with industry bodies to lift standards.

It had a staff member working full time on complaints to the Licensed Building Practitioners (LBP) Board, and was looking at hiring another.

But the LBP regime was in its infancy and ideally the council would like to see a ranking of builders, with those gaining the top status requiring less oversight, McCormick said.