As Christchurch continues to be shaken, heritage experts face some tough decisions.

Early December 2011. Ken Franklin has just made a decision. No more propping or temporary fixes to the Christchurch Arts Centre.

Given the cluster of historical buildings' precarious state, it's either a terrible gamble or a brave vote of confidence in the future. Possibly both. Unlike many landmark heritage buildings, the Arts Centre has survived Canterbury's devastating earthquake swarm and is still standing. Just.

When we speak again, it's a few days after Christmas.


"There is an awful sense of dread. They just come out of nowhere. You never know when it's going to happen next," says Franklin, the Arts Centre director, of the latest quakes that hit on December 23. "We had quite a bit more stone lost from upper levels, especially gables on Worcester Boulevard, but nothing major. We seem to have hung in there. The buildings are still standing. They have shown remarkable resilience to date."

To walk through this complex of gothic stone masonry buildings dating back to 1877, as I did in early December, is to tread the halls, cloisters and quadrangles of what was Canterbury University College and two former secondary schools.

Famous people were here - Ernest, Lord Rutherford, Sir Apirana Ngata and Dame Ngaio Marsh among them. History seeps from these stones, but then you see the present - crack lines, split archways, wrenched piers, walls rent asunder.

"If we do get a shake, stick with me," says Franklin. "Running outside isn't always the right thing to do here." The destructive impact of huge stones crashed down from gable tops indicates what he's talking about. When the circular Observatory tower collapsed in February two contractors were working inside. They followed the safety advice given and moved to the street side of the building. Their car beside the tower was crushed.

The buildings are a patchwork of "make safe" mechanisms: posts under archways, crucially installed in September 2010 and preventing further damage; extensive steel propping against the Clock Tower; a 20-tonne turret on the footpath beside the Great Hall which was fortuitously removed a week before Christmas 2010; the last of the stained glass window finally extricated intact in December last year; shutters over deconstructed gable walls; and threaded tensioned wires running along the Great Hall ceiling pulling its gable ends taut.

"We are feeling quite vulnerable with this building at the moment," says Franklin calmly. "You can see the state of it. It looks reasonable externally but once you get in here you see that it is pretty fragile so the quicker we can get on to that permanent fix the better." The December quakes have hardened his resolve to move forward faster than ever.

This is the harsh reality of heritage recovery in central Christchurch. With so many heritage buildings already gone - in December, before the latest quakes, the Canterbury Earthquake Recovery Authority's (CERA) demolition list designates 124 "demolish", 22 "make safe", and 31 "partial demolish" - those still there are an increasingly rare commodity. Retaining the few remaining in the face of what seems like a scorched earth policy is a thankless, expensive task.

Hence the decision that enough is enough with the propping and that recovery can begin. "We estimate it will cost $240 million to strengthen and repair the site in total," says Franklin. "We're negotiating with two insurance companies - one has pulled out of New Zealand so we're now talking to their head office in the UK. There are a large number of reinsurers lining up behind them so it's a complex situation."


Cash surprise
What's remarkable is that Franklin and the Arts Centre Trust Board - the body charged with preserving and protecting this iconic precinct - have somehow wangled the first $35 million of insurance money. That's enough for repairs and strengthening on the Clock Tower, including Rutherford's Den, and College Hall - a project estimated to take 30 months. Comprehensive insurance cover for the Centre was raised from $95 million to $116 million in January.

In December the Centre received an unexpected boost from the Christchurch Earthquake Appeal Trust - a $14m donation comprising $5 million from American philanthropist Julian Robertson, matched by $5m from the Ministry of Culture and Heritage and $4 million given by Fletcher Building. The extra money means Franklin is already planning stage two of the repairs - estimated at $30 million - for the former Christchurch Boys' High School buildings.

"This series of earthquakes is the worst thing that has ever happened to this place, but in a weird way it's also one of the best things," says Franklin with supreme optimism. "If we can get significant capital and inject that into repairing and helping to preserve these buildings in perpetuity, what a fantastic outcome that would be."

But it will be years before the public will once again enjoy the complex of bars, cafes, restaurants, galleries, studios, theatres, festival and event venues that the Arts Centre was. Heritage repair is a painstakingly slow business. For the Great Hall alone, all the slate roof tiles will be removed and a new plywood diaphragm applied, a concrete ring beam poured at the top of the walls, and the entire structure tied down with post tensioned steel rods.

In the Clock Tower some of the work is even more laborious, with new shear cores created inside the bluestone walls - a process whereby the internal masonry layers of brick or rubble are carefully demolished, replaced with reinforced concrete and then resurfaced with a brick facade on the inside. Elsewhere fibre reinforced polymer wraps - applied to the walls with resin and giving the equivalent strength of 100mm of reinforced concrete- will be used.

All of which takes considerable time and money.

"The reality is that the cost of building these buildings using original technique versus the cost using modern technique is up to four or five times more expensive," says Franklin pointing out the project is costing close to $19,000 a square metre. "If we were starting from scratch with an empty site using modern building techniques, it would probably cost $6,000 a square metre."

Heritage doesn't come cheap. But while the Arts Centre offers a beacon of hope, elsewhere the city is coming to terms with how much is lost. "What you're seeing now is a series of gaps that have appeared - huge slices of the city, huge gaps in people's memories," says architectural historian and heritage planner Jenny May, taking the Herald on a tour of the red zone cordon. "It's about the loss of the memory of the city, the loss of 150 years of the European settlement."

Keeping history safe
May has been trudging the red zone with other Council heritage experts since the second week of the cordon in February, having spent the first week coming to terms with losing both her house and her office.

"There were army tanks and a total unreality. The city was quiet," says May, who immediately began collecting fallen pieces - carved corbels, capitals and the like, before they were lost forever - and putting them in storage. "We know the names of some of the craftsman who carved those and they are works of art in their own right."

Occasionally there are glimmers of hope like New Regent Street where the rows of two-storey Spanish Mission style shops have largely survived, although many of the decorative French ceramic tiles were shaken loose from their shop facades. May and two colleagues collected every tile, conservation wrapped them and put them in storage for later reattachment.

Similar careful conservation work is also happening on a daily basis at the Provincial Council buildings on the corner of Durham and Gloucester streets with two archaeologists on site recording everything removed and packing it on pallets for offsite storage. Like the Arts Centre, the Provincial Chambers - stone and timber buildings constructed between 1858 and 1865 - were designed by Benjamin Mountfort in gothic revival style. Bellamy's - the social and dining facilities attached to the stone chamber and once described as "the pleasantest room in Canterbury" had undergone earthquake strengthening and is in reasonably good condition, as are most of the timber buildings.

The stone chamber, however, suffered an almost complete collapse in February and was damaged further in June, and is now being stabilised and made safe. "It's a careful dismantling stone by stone to retain the magnificence of it all," says May. "There is a hope this may be stable enough to actually consider keeping the lower level of the stone chamber facade and the wish of course is that this will be rebuilt, reinstated where possible and replicated."

Sometimes the gaps in the cityscape deliver a hidden past. We pass an empty lot where the building removed has revealed the tin wall of the adjacent building painted with a huge sign - a picture of a Victorian country house and a painters and decorators' advertisement: "Protect your investment, paint your property regularly and save money."

But mostly there is loss at every turn - St Lukes Church, AJ White's Department Store, the former ANZ Bank, the former Council Civic Offices in Manchester Street, the Regent Theatre in Cathedral Square, the Repertory Theatre and so on.

"Here, I can hardly bring myself to look at it," says May as we turn the corner by Latimer Square into Hereford Street and pass the emptiness where the Occidental once stood. "I spent lot of my working life saving that building and it's gone."

By most accounts the mainly timber building could have been saved. The hotel was established in 1861. Nearby is the Christchurch Club in Worcester Street which is still standing.

"Back then these were the only two building in here in the middle of a paddock," says May. "When the men came into town, they installed wives and children in the hotel and then 'repaired' to their club - sometimes for several days."

Problem in plain sight
The problem with stone and clay brick masonry buildings shaking apart in earthquakes has been known for a long time - at least since the 1931 Hawke's Bay earthquake which ushered in changes to our building codes.

Despite the knowledge of how badly unreinforced masonry buildings perform, little was done to fix the problem. Christchurch has delivered a further lesson - not fixing such buildings means people will die and fixing to 33 percent of new building standards isn't enough.

The earthquakes have also shown that fixing unreinforced masonry buildings to at least to 66 per cent, and ideally to 100 percent, of new building standards does make a considerable difference. One of the main the reasons the Arts Centre remained standing is that parts had earthquake strengthening techniques applied, including vertical post tensioned steel rods and polymer mesh wraps applied to brick work.

It's such learning and advanced earthquake strengthening technology that May and others are working hard to see applied to what's left of Christchurch's heritage buildings. Take the collection of buildings along High Street, beginning with the Mackenzie Willis building on the corner of Tuam Street.

Built in 1910, the building has received a $1 million rescue package donated by Fletcher Building through the Canterbury Earthquake Heritage Buildings Fund to save its facade and anchor the recovery of the Victorian and Edwardian character of the area.

While many of the buildings along High Street are badly damaged, a group of building owners are lobbying CERA hard to have at least the facades retained to create a heritage precinct. Prior to the quake the street had a distinctive ambience with its congregation of boutique and fashion outlets and restaurants and wine bars.

"What has been upsetting was the speed with which the decisions about what buildings were considered dangerous was undertaken," says May of heritage demolitions. "It's about not making decision in haste in the middle of a tragedy. At times I think decisions were made in haste, but we didn't have a blueprint for this either."

The haste with which CERA has proceeded has some calling for a pause. "We say it is time to stop the demolition and take stock of what is left," says an online petition against the destruction, which argues too many decisions have been made on the basis of external assessments by engineers with no experience in the methodologies for strengthening heritage buildings.

The petition, says CERA, has already authorised the demolition of more than 170 listed heritage buildings and non-listed character buildings. "Some of these were very severely damaged, but we believe, on sound engineering advice, that at least 27 of these could have been stabilised, repaired and strengthened to continue as a vital part of the city's history and to contribute to its social and economic well-being."

The concerns tally with the Historic Places Trust which in its submission to the Canterbury Earthquakes Royal Commission points out that of 84 significant heritage buildings in central Christchurch: 31 have been demolished or approved for demolition; 6 partially demolished; 29 secured or made safe; 9 have, or are being, repaired; and 9 have the status of "future unknown". In at least 11 cases of demolition, the Trust had no opportunity for input or its advice for retention was ignored by CERA.

"Generally we haven't had too many complaints from building owners of heritage buildings. It's more from heritage interests," says CERA general manager of operations Warwick Isaacs.

University of Canterbury associate professor of Art History Ian Lochhead says that's the root of the problem - CERA using its legislation to override heritage protection in favour of property interests. "Some heritage building owners have seen the earthquake as an opportunity to quit buildings they felt they had been lumbered with," says Lochhead who is spokesperson for Interests in Conserving the Identity of Christchurch (IConIC), one of the groups behind the petition.

"To date CERA's primary objective has been public safety and everything including heritage has been a long way second to that," says Lochhead. "It's unfortunate they haven't taken a broader remit - looking towards the rebuilding of the city and the role heritage plays in that."

Isaacs says lately CERA has been more relaxed with heritage buildings over the strict timelines of its legislation which, under Section 38, gives building owners 10 days to come up with a demolition or make-safe plan for their buildings.

For the really significant buildings like the Christchurch Cathedral, the Provincial Chambers and the Catholic Basilica he says CERA has let the owners "drive the conclusions to those buildings" and supported the owner to achieve their outcome. "One thing we aren't able to do is leave buildings standing for five or six years while people make decisions about their future because generally those people aren't the building owner," says Isaacs. "The building owners - a lot of them own multiple buildings - need to move on with their lives from an economic point of view otherwise they and the business they own will fail."

What frustrates "heritage interests" is CERA's blindness to the fact that prior to the earthquake, heritage was deemed valuable and had protection in law. Plus that many of the building owners using Section 38s to conveniently exit their liabilities, had in the past received heritage grants for their buildings.

Some building owners are frustrated also that they are unable to convince CERA of the economic benefit in retaining heritage precincts which they believe will be a draw card for businesses, especially tourists.

Isaacs acknowledges "some heritage buildings could have been saved - there is no question about that". But he says in most cases, when given time to come up with a solution, "nothing eventuated." Advocates say a little more patience and co-operation is required.

Petition against heritage destruction - (search "christchurch")

CERA Demolition list:
224 quake-affected buildings in Christchurch have been demolished (by 25 July last year)

85% were old buildings constructed of unreinforced masonry

72% of those partially strengthened (34-67% of new building standards) were seriously damaged or collapsed

24% of those with greater strengthening (67-100% of new building standards) were seriously damaged or collapsed

$1.5 billion: The estimated value of more than 3800 unreinforced masonry buildings in NZ

$2 billion: The estimated cost of upgrading them to make them safe