Rebuilding Mt Pleasant Community Centre
When the Christchurch earthquakes destroyed the existing Mt Pleasant Community Centre, in the eastern Port Hills of Christchurch, it also destroyed theories of existing construction techniques. This raised the need to think about how to live on these shaky islands.
Rebuilding the MPCC meant tossing around innovative construction methods and how these could be utilised to create a building of strong, safe, lean architecture, potentially paving a future pathway. Could this see a critical shift in design approach combining lightweight structures with sustainable materials, digital fabrication, and 3D modeling Building Information Technology?
Chris Moller, a familiar face as host of NZ Grand Designs, and his team from Chris Moller Architecture and Urbanism, CMA+U, won the competition for the new build of the MPCC in late 2013. Submission for building consent was made in mid-2014, followed by an open-book tender process to give the best value to the community given the uncertainty of the rapidly changing post-earthquake marketplace. Digital 3D modeling and the realisation of a full-scale prototype were essential tools in both the design process and construction of the final build.
Lessons from nature inspired new build techniques. The nearby estuary, full of crustaceans and local shellfish, such as crabs, pipi and tuatua, motivated the concept design, resulting in the dramatic, folded wave ‘shell structure’ of the new build.
“Shell architecture is super sustainable being light, strong and material efficient within a compact envelope”, states Moller.
The prefabricated approach to the design kept the number of building packages to three, and contributed to a reduction in the onsite waste. Only the foundations and interior fit out walls were not part of the prefabrication process.
Primary construction elements included the engineered timber-shell structure, metal roof insulated cladding panels, and curtain glazing wall, all of which were prefabricated off–site. These were then pre-assembled in specially made cradles on-site and craned into place. The laminated veneer lumber, LVL, pine panels were sourced locally from the South Island. These and the steel node assemblies required careful prototyping in the design and construction process to test and check the geometries to ensure precise tolerances were achieved.
“The final building is within 3mm across 30m, which is more akin to a precise piece of bespoke furniture”.
The new building is located on the same site as the existing, however re-orientated 90 degrees to embrace the arrival court to the south, and the ever-changing estuary views and sun to the north. With a gradual sloping site, and the previous earthquake damage, the ground required re-piling down to 20m in places to support the new building. It also required substantial and expensive remediation having been previously used as a dumping ground for asbestos and metal.
Given the low level of the site, combined with risk of increased flooding following the earthquakes, and rising sea levels, it was decided to lift the building on a lattice of robust reinforced concrete beams and surround it with an additional rock riprap and perimeter soak trench to protect it from storms. The design also incorporated a number of sustainable heating, cooling, lighting and water features.
The term Community Centre implies a place to all ‘come together’. The design and rebuild of the MPCC has provided exactly that for its close community. It has been a technical architectural achievement, built to stand the test of time, and pushing the boundaries for future construction.
