Heritage Buildings and Earthquakes: Christchurch and Elsewhere
Christchurch heritage suffered a devastating loss in its earthquakes. The Council there (like others) had been remiss in not requiring earthquake strengthening of masonry buildings on a more rapid timetable, but even if it had the result may have still not been happy. The size of the earthquake was such that even when a strengthened building may have stood and saved lives, it was still likely to suffer irreparable damage.
What can be done with damaged buildings? Simply it is not sensible to repair or rebuild them as masonry buildings. That is recreating the danger. One Listener columnist seemed to think this was what heritage advocates wanted and dismissed us all as mad.
In some cases if the facades are reasonably intact it is possible to build a modern frame building behind and then attach the facade to it. Where this is not possible then a replica is the only option – using some of the original fabric where this is recoverable. A replica will have a new moment resisting frame inside it.
Reading the reports from Christchurch it is hard to avoid the view that Christchurch heritage is suffering death by a thousand cuts. The Historic Places Trust has been advocating for particular buildings and for precincts but it does not seem to be winning many battles. CERA seems to be dominated by engineering considerations – does it employ a single heritage expert? Sadly the responsible Minister seems to place no value on heritage.
Christchurch formerly had large areas of low rise Victorian and Edwardian buildings – some of which were in poor condition and in low return uses. Many have gone and it is not realistic to expect that they could return. There is not the economic need for them. Christchurch does have an economic need to recover some of its heritage – it is the character of the city – it is one reason why people live there and visit. What have others done? Perhaps the centres of some German cities are an example. Over the decades after the bombing devastation they recovered selected parts of their cities. Visit them today and some are utterly convincing, some less so, lacking the patina of age. Even then one looks and thinks would one prefer the alternative of ‘all new’? The answer is no.
The officials responsible for Christchurch need a determination not currently apparent to recover heritage. It cannot be left to just safety considerations or to the whims and finances of individual owners. It would seem for instance the Council is wringing its hands over the Cathedral rather than leading.
There should be a list of buildings that are “must saves”. There should be a precinct or two that are “must recovers”. Christchurch deserves as much.
Elsewhere: The Royal Commission on the Christchurch earthquake has been hearing of the number of masonry buildings elsewhere in New Zealand that are at risk. One advocate there said the solution to them all was to pull them down. Other commentators seem to think what is proposed is the same standard for all of New Zealand when the risk is lesser in some parts. Not so, the design standard is differentiated to different places. The requirement is to strengthen to a proportion of the local standard. Local authorities are required to nominate a standard – not less than 33% and to give a deadline. Is this a case for subsidiarily – what do the local authories add in this case – other than be a target for owner lobbying? Already we see Auckland Council deciding on secrecy for its at risk building lists. Surely there is a case for an overall national standard and a timetable.
Where Councils can be involved is just as it is in Canterbury – deciding locally what is a ‘must save’ building and what is a must protect precinct, where the cost of strengthening is one that must be borne.
With some engineering the response is targeted to not only the risk but the consequence. Some of this is done already; schools and emergency facilities are seen as higher consequence and have a higher standard. Surely there is a case for this to extend to low occupancy high heritage value buildings – where the intrusiveness of strengthening to a high standard would greatly lessen their heritage value. Not fail to strengthen them – just accept more risk.
Christchurch heritage suffered a devastating loss in its earthquakes. The Council there (like others) had been remiss in not requiring earthquake strengthening of masonry buildings on a more rapid timetable, but even if it had the result may have still not been happy. The size of the earthquake was such that even when a strengthened building may have stood and saved lives, it was still likely to suffer irreparable damage.
What can be done with damaged buildings? Simply it is not sensible to repair or rebuild them as masonry buildings. That is recreating the danger. One Listener columnist seemed to think this was what heritage advocates wanted and dismissed us all as mad.
In some cases if the facades are reasonably intact it is possible to build a modern frame building behind and then attach the facade to it. Where this is not possible then a replica is the only option – using some of the original fabric where this is recoverable. A replica will have a new moment resisting frame inside it.
Reading the reports from Christchurch it is hard to avoid the view that Christchurch heritage is suffering death by a thousand cuts. The Historic Places Trust has been advocating for particular buildings and for precincts but it does not seem to be winning many battles. CERA seems to be dominated by engineering considerations – does it employ a single heritage expert? Sadly the responsible Minister seems to place no value on heritage.
Christchurch formerly had large areas of low rise Victorian and Edwardian buildings – some of which were in poor condition and in low return uses. Many have gone and it is not realistic to expect that they could return. There is not the economic need for them. Christchurch does have an economic need to recover some of its heritage – it is the character of the city – it is one reason why people live there and visit. What have others done? Perhaps the centres of some German cities are an example. Over the decades after the bombing devastation they recovered selected parts of their cities. Visit them today and some are utterly convincing, some less so, lacking the patina of age. Even then one looks and thinks would one prefer the alternative of ‘all new’? The answer is no.
The officials responsible for Christchurch need a determination not currently apparent to recover heritage. It cannot be left to just safety considerations or to the whims and finances of individual owners. It would seem for instance the Council is wringing its hands over the Cathedral rather than leading.
There should be a list of buildings that are “must saves”. There should be a precinct or two that are “must recovers”. Christchurch deserves as much.
Elsewhere: The Royal Commission on the Christchurch earthquake has been hearing of the number of masonry buildings elsewhere in New Zealand that are at risk. One advocate there said the solution to them all was to pull them down. Other commentators seem to think what is proposed is the same standard for all of New Zealand when the risk is lesser in some parts. Not so, the design standard is differentiated to different places. The requirement is to strengthen to a proportion of the local standard. Local authorities are required to nominate a standard – not less than 33% and to give a deadline. Is this a case for subsidiarily – what do the local authories add in this case – other than be a target for owner lobbying? Already we see Auckland Council deciding on secrecy for its at risk building lists. Surely there is a case for an overall national standard and a timetable.
Where Councils can be involved is just as it is in Canterbury – deciding locally what is a ‘must save’ building and what is a must protect precinct, where the cost of strengthening is one that must be borne.
With some engineering the response is targeted to not only the risk but the consequence. Some of this is done already; schools and emergency facilities are seen as higher consequence and have a higher standard. Surely there is a case for this to extend to low occupancy high heritage value buildings – where the intrusiveness of strengthening to a high standard would greatly lessen their heritage value. Not fail to strengthen them – just accept more risk.