The building destroyers
A taut voice over the phone reports there has been an 'incident' at the former Government Life building, the 1960s tower block of fabled ugliness in Cathedral Square which is being gutted of asbestos ahead of its demolition in a month or two.
Helina Stil, health and safety manager of Nikau Contractors, swings her Range Rover - numberplate 'DSTROY' - in a tight circle and scoots back across Christchurch's central city red zone to discover what has happened.
Hopefully nothing bad. But bringing down large buildings is inherently a dangerous business.
No-one wants any more lives claimed as a result of the Canterbury earthquakes. In eastern Turkey, where there are even more buildings to be levelled as a result of its own magnitude 7.2 earthquake in 2011, a number of workers have been killed in demolition accidents.
As we arrive outside Government Life, a work gang of rugged Samoans and Tongans, dressed in gumboots and blue stubbies, have filed out and are calmly tucking into their lunchboxes.
A sixth member of their group, a slightly-built Ethiopian who arrived in Christchurch by way of Sudan, sits on a salvaged office chair parked inside a Cathedral Square phone booth, keeping himself out of the chilly breeze as he eats his sandwich.
Stil says they are good guys, all recruited locally. It is grunt work cutting out asbestos-lagged pipes. And, how can she put this politely, it tends to be Pacific Islanders and immigrants doing it because most Kiwis will not tolerate the masks, the regulations, and the sheer physical effort.
'For every 10 you employ to do an asbestos job, eight will find it too difficult. There are a lot of people who decide there's an easier way of earning money and will chuck in the towel after just a couple of hours.'
The 11-storey Government Life building is another of those Christchurch multi-storeys where for months puzzlingly little appears to have been happening - the demolition of the town looked on hold - yet quietly the building was being hollowed out from the inside.
Stil says you can do a dirty demolition. Just crash it all down and cart it away. But the Canterbury Earthquake Recovery Authority (Cera) is insisting things are done properly.
So first there is the soft strip where carpets and partitions are ripped out, wiring and window frames are recycled for their metal. Workers whiz around inside the buildings in little four- tonne Bobcat skid steer loaders, filling skips.
Then after that, the big boys' toys can move in to bowl the building itself. Up above 15 storeys, the buildings are 'cut and craned'. Concrete-cutting teams slice through the columns and spidery hammerhead tower cranes hoist them away, a length at a time.
But below 15 storeys, Nikau can roll in its prized bit of kit, the $3 million behemoth 'Twinkle Toes', a 65 metre ultra-high reach excavator it had shipped over from Britain last October. It's a rock star of a machine, the biggest of its kind in the southern hemisphere and third largest in the world.
With its dinosaur-like jaw attachment, Twinkle Toes can gnaw away the remains of a building in double-quick time, crunching the concrete into small lumps.
Stil says it looks inefficient, but it breaks the building into rubble that can go directly back into the site to fill up the foundation hole. No need to truck it to the dump.
The Government Life demolition is trickier than most because of the asbestos insulation. Stil says it has to be completely cleaned up inside before Twinkle Toes starts its work.
So the first step is to seal the building airtight, screwing shut and siliconing its windows, blocking doorways and other gaps with polythene sheeting.
'The whole thing is made what we call a removal enclosure. It has a negative pressure ventilation system going all through it to take any airborne fibres out of the air while the asbestos is being removed.
'Asbestos is just like any other hazard that you'll find on a construction site. As long as it's managed well and the controls are in place it's not going to create a problem,' Stil reassures.
Having hurried off to one of the containers used as a site office to investigate the accident report, she returns looking relieved. Only a minor drama. A worker dropped a pipe on his hand. He has it iced and elevated, but nothing apparently broken.
We hop back in her car to continue the tour of a city business district that's fast disappearing.
It seems a perverse form of prestige. All the Christchurch landmark buildings coming down are proudly emblazoned with the banners of their destroyers. And Auckland's Nikau Contractors has had its name up on more than most.
The demolition specialist turns out to be very much a family business. Founded by mum and dad, Diana and John Stil - Maori with dashes of Dutch and Scottish ancestry - all the children and plenty of cousins are involved, says Helina Stil.
Brother John Paul is senior project manager, brother Michael is contracts manager, and sister Janine is administrative director. 'We've all got different jobs so we don't butt heads,' Stil laughs.
The kids were on the heavy machinery from a young age, she says. One difference about demolition work is the need to be able to turn a hand to any task on a site.
'A genuine demolition person has to be multi-skilled. It's not about sitting in an excavator all day. They've got to have skills in communication, health and safety, environmental issues. They can have qualifications in things like rigging, cranage, confined spaces.
'The perception is that all you need to get into the demolition business is a wheelbarrow and a sledge hammer, but it's a lot more involved than that.'
Stil admits her own move into the health and safety role might have been hastened by her graunching the gearboxes on a few of the family's vehicles in her early days.
'I did try my hand at the truck driving but it didn't work out that well. The pedals were too heavy for my legs.'
However, Stil says women also seem to take that aspect of the work more seriously. Nikau employs a squad of women with clipboards as "safety champions" to watch over its various sites within the red zone.
Stil arrived in Christchurch the day after the February 22 quake. 'Mum and I were in Wellington when it happened. There weren't any planes going so we came down on the next ferry.'
Stil says many other demolition workers turned up without prompting, knowing their skills and equipment would be needed in the rescue operations.
'It was a privilege but also very traumatising. I saw many good men in tears.'
Since then, with some 1600 buildings to come down, the central city has been given over to the country's demolition industry.
It is surreal even for the contractors themselves. Stil says they cannot help but keep a fascinated eye on how their competitors are doing, what techniques they are employing. It is not just a business opportunity but an educational experience.
'You've got Blakely's working next door to Southern's, working next door to Ward's, working next door to us," she says.
"What we've got here is the world's biggest training ground for demolition. In Auckland we might do six or seven multi-storeys a year. Here we are doing that every two months.'
Nikau has had to expand rapidly, buying new machinery like Twinkle Toes and recruiting 40 staff locally.
In fact, says Stil, the work is already slowing down.
At the start of the year, the company would have had 20 to 30 smaller buildings on the go. All that has now been cleared away and with only the tallest towers left, to the contractors, the red zone suddenly feels much quieter than it probably appears to onlookers watching from the other side of the cordon fencing.
But Stil says Nikau expects to remain a presence in Canterbury for the rebuild and - having already been up for a few international industry awards - it hopes to have the CV to expand to other countries like Australia.
We arrive at another collection of containers acting as the site office of the 21-storey PricewaterhouseCoopers (PWC) office block in Armagh Street - by floor space, the biggest of all the demolitions taking place in central Christchurch.
Nikau is doing the job in partnership with construction firm, Arrow International. Pinned up on a wall of the office is a neat architect's blueprint showing exactly how the building is to be tackled, stage by stage.
Yes, you would be surprised how carefully planned the whole operation has to be, says Nikau project manager Jean-Paul Bezzina. A South African who has been a freelance contractor in New Zealand for 14 years, he says every large building is different. Work on PWC was delayed almost two months because of the challenges in getting Cera's approval for a demolition methodology, among other issues.
Bezzina says for a 1980s building, PWC is an unusual design because it has a particularly heavy external frame with metre-square columns of concrete, then steel spans holding up the floors.
'All the strength is in the perimeter beams.' Most other buildings of the era are a lighter- weight structure anchored by the stiff core of their lift shafts.
Solid lift shafts make for a handy disposal chute for the demolition debris, says Bezzina. 'So when we did the strip-out at PWC, we had to use two cranes to crane everything out in skips through the exterior face of the building.'
The earthquake damage also meant the building needed to be strengthened before it could be pulled down.
Bezzina says PWC stood up remarkably well to the quakes, but levels five to eight were crushed as the whole structure got lifted then dropped down on itself again.
'We had to put in temporary shoring and propping before our workers could even go in.'
The weaknesses dictated which side needed to be started on first. The deconstruction plan called for the building to be stepped down like a pyramid in alternating fashion, four levels of one corner, then eight of the next, says Bezzina.
'Obviously we have to avoid an uncontrolled collapse. So we are going around it, doing a shallow quadrant, then a deep quadrant, a shallow quadrant, then a deep quadrant, so there is not too much load placed all on one side of the building.'
He says nerves were tested when demolition started in March.
'We had a 5.2 shake on the Friday afternoon when I was on the top of the building. It really moved. We had to run down 20 flights of stairs, but we managed to evacuate the entire building in four and a half minutes, almost 30-odd staff.
"So the boys there have had some interesting experiences.'
Once demolition began, Bezzina says they managed to make up for lost time. And time is money, especially in a city where there are other projects to get on to.
The internal strip-out was going on from April through to July, seven days a week, under lights late into the evening. While one gang worked from the top floor down, another gang was working from the bottom floor up.
Bezzina says this was one of many innovations the team adopted.
'It really is like demolition school here. We've been learning all sorts of new ways of doing things.'
When the cut and craning began, Bezzina says the team discovered another time-saver by using mechanical picks to hack out the thick columns.
'Rather than saw cutting everything as usual, we ended up using small four-tonne excavators with a breaker attachment.'
The cut and craning operation to remove the top five floors took seven weeks. And now Twinkle Toes has been wheeled in to polish off the remaining 15 floors plus basement in about three or so.
'You can see how having the high reach really pays for itself,' says Bezzina.
Time to meet the real star of the outfit. Taking a break while one of the smaller excavators tidies up the site for him, Twinkle Toes' driver Bill Robinson is relaxing in a restroom container.
Robinson, from Birmingham, has been with 220-tonne Twinkle Toes (called 'The Beast' in the England) since it was first commissioned four years ago. Robinson is about the only person with the licences and experience to operate it.
It is harder than it looks, he says. The three-section extending 65m boom dangles a 'muncher' at the end which weighs a couple of tonnes. For shorter-range work, this can be stepped up to a four- tonne attachment.
'On a normal excavator, the arm doesn't flex. But my arm is moving up to two metres each side. It's flexing all over the place all the time, because if it didn't bend, it'd break.'
So, he says, imagine wobbling a floppy stalk about in the sky and bringing its jaws precisely into place as the nor-westers get up. And it all has to be done line-of- sight. Robinson does not have a camera at the top of the boom.
'Some do. But a camera's not a working tool because with the amount of water spray and concrete dust up there, in five minutes the lens would be covered.'
Instead he relies on squinting 15 storeys upwards through the thick glass and metal bars of his cab's protective cage. Working a 10-hour day, six days a week, it demands total concentration.
'On a normal machine, I could be listening to the radio, thinking about my tea. But at that kind of height, you're watching all the time. And at the end of the day, you're knackered.'
Before a demolition even starts, Robinson says he walks the building to visualise his plan of attack and figure out how its fabric will react.
There is a lot of responsibility on his shoulders. The aim is to crunch the structure into rugby ball-sized lumps, but sometimes bigger chunks are unavoidable. 'And it may sound silly, but concrete does bounce - it can bounce a fair way.'
The Christchurch job means Robinson will be a long time away from his family. He gets a couple of breaks a year, in June and at Christmas.
And in Christchurch, he lives in a rented house in Riccarton with a bunch of the other Nikau contractors - Bezzina occupies the room next door.
But he says that is what life is like for many with specialist skills in the construction industry. He is well used to the international travel.
'I was saying to my wife, we've been married about 31 years and I've only been home for about 10 of 'em.'
Robinson says the mental challenge of picking apart a building means he does not get bored. And he admits, like all demolition workers, there is a lot of fun in knocking things down.
The call comes that Robinson can get back to work. A rubble platform has been built at one end of the site so Twinkle Toes can reach one last tricky piece of wall.
PWC is now nearly done and Robinson recites the list of remaining Christchurch landmarks still ahead. The Government Life building, but also the Farmers car park, Holiday Inn and Ngai Tahu's head office, Te Waipounamu House in Hereford St. Probably a few others too.
So the pattern will continue. The machinery that spells the end will rumble across the city from one site to the next. What for many months was taking longer than expected to happen will suddenly happen much faster than can be believed.
Blink and in a matter of weeks another familiar building will have been plucked from the Christchurch skyline, leaving only the hollow emptiness of a levelled foundation. And no longer even the passing entertainment of the busy cranes and excavators.