Architects have incorporated cardboard tubes and shipping containers into a large A-frame structure that will serve as a temporary cathedral in Christchurch, New Zealand, as the city recovers from a devastating earthquake. Courtesy of ChristChurch Cathedral
In Christchurch, New Zealand, an inspiring cathedral made of cardboard is set to rise from the rubble, a symbol of a new beginning in a hard-hit city.
May 8, 2012—Near the heart of Christchurch, New Zealand, construction will begin soon on a unique cathedral, complete with a dramatic 79 ft high roof made of cardboard tubes. It is the product of a chance contact between a reverend in the Anglican Church whose congregation was displaced in a devastating earthquake and a Japanese architect who has made a reputation designing beautiful temporary buildings in the wake of natural disasters.
“I was reading a design magazine (URBIS) in May 2011 and saw a paragraph on Shigeru Ban, also a small picture of a church he built in Kobe, Japan, after an earthquake there in 1995,” remembered the Reverend Craig Dixon, ChristChurch Cathedral, in written comments to Civil Engineering online. “I emailed Shigeru and he agreed to assist.”
Ban designed a large A-frame structure on a concrete foundation, stabilized by carefully disguised shipping containers, which will also provide space for a kitchen, offices, and storage. The roof of the structure utilizes cardboard tubes, locally sourced. The tubes will be 600 mm in diameter, with a wall thickness ranging from 8 mm to 10 mm, according to Peter Marshall, the managing director of Warren and Mahoney Architects Ltd., Christchurch, New Zealand, who provided written comments to Civil Engineering online.
The cathedral will seat about 700, with dimensions that are based on the proportions of the nave of the original cathedral, currently being deconstructed. The building will narrow slightly at the front, affording parishioners a dramatic view of the cardboard tubes and an elevated ceiling above the altar.
Sagging of the tubes has been a concern in the design phase. Each tube will be about 20 m long, composed of two sections joined together with a timber splice.
The dimensions of the cathedral, which will seat about 700, are
based on the proportions of the nave of the original cathedral,
which is currently being deconstructed. The building will narrow
slightly at the front, affording parishioners a dramatic view of the
cardboard tubes and an elevated ceiling above the altar. Courtesy
of ChristChurch Cathedral
“The main design challenge centered around the use of cardboard tubes, initially as the primary structure, with some composite action arising from small timber trusses fixed to each tube,” Marshall said. “Further structural analysis showed the undue sag would still occur, so the truss was deleted and a timber LVL [laminated veneer lumber] beam inserted within the tube.
“An analysis of potential sag will be made once the first sample is produced,” Marshall said.
“The tubes are coated with polyurethane, with careful attention given to the exposed ends,” Marshall added. “We are considering whether the interior surface requires coating as well, and whether an antigraffiti coating is required.”
Marshall said the tubes will be secured to a steel beam that runs above ordinary shipping containers that are being used at the base of the structure, and will be secured at the top to a timber ridge beam. The tubes will be joined with purpose-made galvanized steel brackets. Metal bracing straps will provide lateral stability.
Stability is an important concern in Christchurch, which is still being rocked by aftershocks. The site is also exposed to strong northwest winds.
Ban has designed many high-profile temporary structures in Turkey, China, Haiti, and Japan following disasters. His pro bono work on the cathedral in Christchurch is symbolic of a bond the residents of Japan and New Zealand feel about the powerful earthquakes they both face.
“Our links with Japan [are] important,” Dixon said. “We had Japanese USAR [urban search and rescue] teams assist in New Zealand after our earthquake on February 22, 2011, and a New Zealand USAR went to assist in Japan after their devastating tsunami in March 2011.”
Although paper and cardboard are unconventional building materials, they provide clear benefits for temporary structures in areas struggling to recover after an earthquake.
“The strength of a building has nothing to do with the strength of the material,” said Ban in a fact sheet about the project. “Even concrete buildings can be destroyed by earthquakes very easily. But paper buildings cannot be destroyed by earthquakes.
“Normally after disasters the price of building materials goes higher, but since this is not a traditional building material, it’s very easy to get,” Ban added.
The earthquake that displaced the ChristChurch Cathedral congregation in February 2011 was a 6.3 on the Richter scale, which belies the fact the temblor registered one of the strongest peak ground acceleration numbers—2.2g— ever recorded. The quake killed 185 people and damaged thousands of buildings.
The striking 79 ft tall cathedral, which was designed to last for 20
years, will rest on a concrete foundation and will be stabilized by
carefully disguised shipping containers. Courtesy of ChristChurch
The February temblor destroyed the cathedral’s famous spire, which had been repaired following earthquakes in 1888 and 1901. Although the walls remained intact, they were heavily damaged. Questions about a project to restore the structure became moot in June when a powerful aftershock further damaged the building.
“The cathedral congregation has found it a great challenge to have no home,” Dixon said. “This will give them a place to belong which is innovative and exciting. A step on the way to rebuilding the Cathedral in the Square and a sign of hope. For the community, this will be one of the few venues available for concerts and events in the city. It will be one of the very first rebuilds following the earthquakes. A sign of hope, too, for the city.”
Although the building is considered a temporary home for the cathedral’s parishioners and makes extensive use of cardboard as a building material, the structure will likely stand for more than 20 years. The cathedral will be constructed south of Latimer Square, on the former site of St. John's Anglican Church, which was also destroyed in the February 2011 earthquake. The building was deconsecrated and dismantled.
Geotechnical analysis is under way at the site, in preparation for an accelerated construction schedule, the $4-million to $5-million structure expected to be complete in November 2012.
Dixon said that although the ChristChurch Cathedral will be rebuilt, the timing of that is unknown. The damaged building is still being removed from the site.
“That will take close to a year,” Dixon said. “Beyond that, no one knows. The church is getting together design guidelines but post that, it’s anyone’s guess.” Current plans are for the building to become a parish church for the St John's Anglican Church community in the central city.
“Their church was also destroyed,” Dixon explained. “It is on their land that we are placing the Cardboard Cathedral. This will take place after 10 years.”
Marshall said he is humbled to be working on the project, contributing something positive to the hard-hit city as it begins to rebuild.
“We relish a new opportunity, and a new way of looking at structure, architecture, and space. In this small way we can perhaps bring another milestone to our broken city,” Marshall said. “Being involved with Shigeru Ban has been a unique experience and his skill, experience, and humility has shown itself through the project.
“At the community level we have been privileged to help bring the project to this point and are looking forward to detailing the project, guiding it throughout the building consent process, and working closely with the contractor in bringing this unique building to realization,” Marshall added. “It is an important project at many levels; it will be symbol of hope; it will provide a place of gathering and worship; it will be an attraction in its own right; and it is a building that can be passed on to the parish in due course.”