Scoop has an Ethical Paywall
Work smarter with a Pro licence Learn More
Parliament

Gordon Campbell | Parliament TV | Parliament Today | Video | Questions Of the Day | Search

 

New foundation design categories for Canterbury

Hon Gerry Brownlee
Minister for Canterbury Earthquake Recovery
Hon Maurice Williasom
Minister for Building and Construction

28 October 2011 Media Statement
New foundation design categories for Canterbury

Three new categories for residential foundation design have been developed and will be required for repairing and rebuilding homes in Canterbury following the earthquakes of 2010 and 2011, it was announced today.

Canterbury Earthquake Recovery Minister Gerry Brownlee said the foundation designs apply to the flat land in the residential green zone in Canterbury, which has now been divided by engineering experts into three new technical categories (TC1, TC2 and TC3).

The categories, and the areas they apply to, are based on ground conditions, including the susceptibility to liquefaction, and the extent of land and building damage caused by the earthquakes.

"Following the damaging earthquakes in Canterbury, extensive scientific and geotechnical investigation and research has been undertaken by a range of experts to identify land issues and ways to reduce the risk of injury to people and damage to homes in any future earthquakes," Mr Brownlee said.

"This is part of ongoing work to improve building standards in New Zealand and the Government's coordinated response to long-term recovery in Canterbury. The information released today will allow homeowners with damaged properties in the residential green zone to get on with the process of repairing or rebuilding their homes with greater confidence," he said.

Advertisement - scroll to continue reading

Are you getting our free newsletter?

Subscribe to Scoop’s 'The Catch Up' our free weekly newsletter sent to your inbox every Monday with stories from across our network.

The three new technical categories are part of the Department of Building and Housing (DBH)'s updated guidance for repairing or rebuilding houses in Canterbury following the earthquakes.

DBH first issued guidance for repairing or rebuilding homes in land damaged areas of Canterbury in December 2010 following the 4 September 2010 earthquake. This guidance is currently being updated following two more damaging earthquakes in Canterbury on 22 February and 13 June 2011.

Building and Construction Minister Maurice Williamson said the three technical categories relate to the performance of flat land in the earthquakes and its susceptibility to liquefaction in any future significant earthquakes.

A map has been released today with the three different technical categories of land colour coded on it - TC1 is grey, TC2 is yellow, and TC3 is blue.

"The good news is homeowners whose property is in TC1 or TC2 with foundations that require repairing or rebuilding, they can get on with the process with confidence. The only further site-specific geotechnical investigation required is the simple shallow soil strength testing which is standard for all homes. A range of standard solutions are available for the repair and rebuilding of foundations in these areas.

"Property owners in TC3 who need to carry out repair or rebuilding of foundations can do so, but they will require site-specific geotechnical investigation and specific engineering foundation design," Mr Williamson said.

• Technical Category 1 (TC1)
Properties in TC1 (grey) are unlikely to experience significant land damage from liquefaction in future earthquakes. Standard concrete slabs and timber floors are acceptable for foundation repairs or rebuilds.

• Technical Category 2 (TC2)
For properties in TC2 (yellow), minor to moderate land damage from liquefaction is possible in future significant earthquakes. Lightweight construction, for example corrugated iron not tiled roofs, or enhanced foundations such as more robust floor slabs that better tie the structure together will be required for foundation repairs or rebuilds.

• Technical Category 3 (TC3)
For properties in TC3 (blue), moderate to significant land damage from liquefaction is possible in future significant earthquakes. Foundation solutions should be based on site-specific geotechnical investigation and specific engineering foundation design where foundation repairs or rebuilds are needed. This might involve deep pile solutions.

For properties not in these categories, normal consenting procedures will apply. This applies to non-residential properties in urban areas, properties in rural areas or land outside the areas which have been mapped for land damage and properties in the green zones on the Port Hills and Banks Peninsula.

DBH is currently undertaking a trial of foundation systems in Christchurch to test the feasibility and costs of other foundation solutions for properties in TC3 that need to have their foundations repaired or rebuilt due to earthquake damage.

Some of the techniques proposed in the trial have been used in roading but they have not previously been used in residential construction. These techniques have the potential to offer cost effective alternatives to deep pile solutions. The trial is expected to be completed, and peer reviewed internationally with the results released by mid-December 2011. Updated guidance for repairing or rebuilding houses and design guidance in Technical Category 3 is then expected to be issued by the end of February 2012.

A summary of the DBH guidance for repairing or rebuilding houses following the earthquakes in TC1 and TC2 categories is available on www.dbh.govt.nz/canterbury-earthquake-residential-building

Homeowners can find out what technical category their property is in by visiting the CERA land information website: www.landcheck.org.nz. The new technical categories only apply to residential properties in the green zone with foundations that are required to be repaired or rebuilt due to earthquake damage or for future major renovations or new builds.

DBH is one of a number of government departments working with the Canterbury Earthquake Recovery Authority (CERA) on rebuilding greater Christchurch and its surrounds, and supporting the welfare of its residents. For more information visit www.cera.govt.nz

ENDS

© Scoop Media

Advertisement - scroll to continue reading
 
 
 
Parliament Headlines | Politics Headlines | Regional Headlines



Gordon Campbell: On Dune 2, And Images Of Islam


Depictions of Islam in Western popular culture have rarely been positive, even before 9/11. Five years on from the mosque shootings, this is one of the cultural headwinds that the Muslim community has to battle against. Whatever messages of tolerance and inclusion are offered in daylight, much of our culture tends to be hostile to Islam when we’re sitting in the dark, with popcorn.
Any number of movie examples come to mind, beginning with Rudolf Valentino’s role (over a century ago) as the romantic Arab hero in The Sheik...
More


 
 


Government: One-stop Shop Major Projects On The Fast Track

The Coalition Government’s new one-stop-shop fast track consenting regime for regional and national projects of significance will cut red tape and make it easier for New Zealand to build the infrastructure and major projects needed to get the country moving again... More

ALSO:


Government: GPS 2024: Over $20 Billion To Get Transport Back On Track
Transport Minister Simeon Brown has released the draft Government Policy Statement (GPS) on Land Transport, outlining the Coalition Government’s plan to build and maintain a transport system that enables people to get to where they need to go quickly and safely... More

ALSO:

Government: Humanitarian Support For Gaza & West Bank

Winston Peters has announced NZ is providing a further $5M to respond to the extreme humanitarian need in Gaza and the West Bank. “The impact of the Israel-Hamas conflict on civilians is absolutely appalling," he said... More


Government: New High Court Judge Appointed

Judith Collins has announced the appointment of Wellington Barrister Jason Scott McHerron as a High Court Judge. Justice McHerron graduated from the University of Otago with a BA in English Literature in 1994 and an LLB in 1996... More

 
 
 
 
 
 

LATEST HEADLINES

  • PARLIAMENT
  • POLITICS
  • REGIONAL
 
 

InfoPages News Channels


 
 
 
 

Join Our Free Newsletter

Subscribe to Scoop’s 'The Catch Up' our free weekly newsletter sent to your inbox every Monday with stories from across our network.