New Zealand has a long tradition of using light timber frame for construction of its domestic dwellings. After the most recent earthquakes (e.g. Canterbury earthquakes sequence), wooden residential houses showed satisfactory life safety performance. However, poor performance was reported in terms of their seismic resilience. Although numerous innovative methods to mitigate damage have been introduced to the New Zealand community in order to improve wooden house performance, these retrofit options have not been readily taken up. The low number of retrofitted wooden-framed houses leads to questions about whether homeowners are aware of the necessity of seismic retrofitting their houses to achieve a satisfactory seismic performance. This study aims to explore different retrofit technologies that can be applied to wooden-framed houses in Wellington, taking into account the need of homeowners to understand the risk, likelihood and extent of damage expected after an event. A survey will be conducted in Wellington about perceptions of homeowners towards the expected performance of their wooden-framed houses. The survey questions were designed to gain an understanding of homeowners' levels of safety and awareness of possible damage after a seismic event. Afterwards, a structural review of a sample of the houses will be undertaken to identify common features and detail potential seismic concerns. The findings will break down barriers to making improvements in the performance of wooden-framed houses and lead to enhancements in the confidence of homeowners in the event of future seismic activity. This will result in increased understanding and contribute towards an accessible knowledge base, which will possibly increase significantly the use of these technologies and avoid unnecessary economic and social costs after a seismic event.
Flooding and liquefaction surround a house in Richmond. Bricks have fallen from the walls of the house, exposing the wooden framework beneath.
Damage to a house in Richmond. Bricks have fallen from the walls, exposing the wooden framing beneath.
Damage to a house in Richmond. Bricks have fallen from the walls, exposing the wooden framing beneath. Power lines between the house and a power pole have been stretched taut. The photographer comments, "The house and power pole have moved, stretching power lines taut as a guitar string".
A spray-painted message on a wall of Englefield Lodge reads "We will try to save this house." Wooden bracing supports the wall. The photographer comments, "A bike ride around the CBD. Englefield, Christchurch's oldest house in Fitzgerald Ave".
Damage to Englefield Lodge on Fitzgerald Avenue. A pile of bricks lies in front of the house, windows are boarded up, and wooden bracing is propping up the walls. A spray-painted message on a wall reads "We will try to save this house." The photographer comments, "A bike ride around the CBD. Englefield, Christchurch's oldest house, in Fitzgerald Ave".
Damage to a house in Richmond. Bricks have fallen from the walls onto the driveway, and a large gap between the concrete foundation and the wooden framing shows how much the house has moved. The photographer comments, "The foundations and brick cladding moved, but the timber wall remained in position. The gap grew to over 400mm by the time the house was demolished.
Damage to a house in Richmond. The foundation is all that remains of one room, and the exposed interior wall has been covered with builders' paper for protection. Weeds grow between cracks in the concrete patio. The photographer comments, "Revisiting our abandoned house. Cracked patio. The wooden floor is all that remains of a sunny living space with bifold doors, opening the house to the garden. This was so broken on 4/9/10 that it was immediately demolished".
Damage to a house in Richmond. Part of the brick wall has slumped to one side, leaving a visible gap between the wall and a windowframe. Broken wooden framing can be seen in the gap. The photographer comments, "Cracking in the external brickwork".
Damage to a house in Richmond. Bricks have fallen from a wall, exposing the wooden framing beneath. The photographer comments, "The foundation and a section of the wall of the dining room have shifted and cracked. The dining room floor is very springy".