In challenging economic times New Zealanders are, more than ever, acknowledging the economic and sustainability benefits of renovation versus building new. It is encouraging see building owners are not only saving money and reducing the amount of extra waste that ends up in our landfills, but they are also preserving and protecting the cultural heritage of our country by restoring buildings of historical importance.
The AMP Society Building at 86 Customhouse Quay in Wellington is a great example of this. The AMP Society Building at 86 Customhouse Quay in Wellington is a great example of this. After a year on site the final finishing touches have been made and the last of the scaffolding has come down to reveal the glory of the building’s freshly refurbished façade. Designed by architects Clere and Clere, the AMP Society Building carries a Category I listing with the New Zealand Historic Places Trust and several protections under the Wellington City Council District Plan. It is also one of the very few examples of a Sydney Sandstone building in New Zealand.
Having stood since 1928 with minimal exterior maintenance, it is no surprise that the building façade was showing significant signs of deterioration by its 80th birthday. The exterior of the building was generally stained and in need of cleaning and repointing in its entirety. Excessive water ingress through horizontal surfaces, via failed pointing and broken masonry, was the main cause of deterioration. This resulted in the formation of crusts which were spalling and breaking away, and also caused significant staining, efflorescence, swelling and blistering of the stone. There were also significant areas of mechanical damage and microbiological growth, and concerning patterns of cracking developing on one façade which indicated a problem with the structural steel beneath.
Restoration work followed the production of a detailed Façade Condition Report a number of years ago that assessed each stone and made recommendations for repair. In 2009 the building owners agreed to carry out façade refurbishment works to prevent ongoing exponential decay of the building fabric. After sourcing supply of closely-matching Sydney Sandstone and an expert stone masonry firm, Traditional Stonemasonry Ltd, to carry out the refurbishment works, work commenced in September 2010.
The façade restoration works undertaken have included:
- Dismantling and removal of cracked sandstone to determine the cause of damage
- Treatment of structural steel behind cracked stone
- Replacement of cracked or damaged stone with new Sydney Sandstone
- Dismantling and removal of terra cotta pieces to determine the cause of damage
- Production of moulds and new terra cotta pieces to affect repair, made in the UK
- Dressing back of stones where significant surface damage was evident but replacement was not required
- Complete cleaning and repointing of the building
- Installation of lead weatherings to all horizontal surfaces to prevent ongoing water ingress
- Colouring of the new stone and dressed-back areas to match existing stone
Significant repair work was also undertaken to the statue atop the corner of the building, a painted copper replacement of the marble original that was in notably bad condition. Investigations were made to determine how the statue had been formed, what was inside it, and how best to repair it. These investigations revealed that the statue had been made in three pieces that were fitted over a steel frame and, once assembled, had been largely back-filled with concrete. The steel frame was therefore rusting, placing pressure on the concrete which, in turn, was placing pressure on the copper, causing screws to pop out and joints to open.
Repair works to the statue included:
- Removal of the front entablature panel including loose lettering
- Cutting-back of the concrete fill
- Excavation of corroding steel reinforcement
- Installation of a new section of steel frame Repair to damaged letters and popped screws
- Clearing and refilling of the two major joints in the statue
- Removal of all loose and flaking paint and sealing of these areas
- Complete repainting of the statue
The project will be completed with the handover of documentation recording all the alterations made, and recommendations for cyclical maintenance.
It has been a privilege for S&T to lead this work, ensuring one of Wellington’s most unique and significant heritage buildings is conserved for years to come.
For more information on S&T’s work on historic building renovations, please contact us