135-141 Jackson Street, Petone
A clear vision for the buildings’ upgrade
Situated on a prominent corner, the building façades at 135-137 and 139-141 Jackson Street are an important contributor to the heritage streetscape. Owners Geoff Wylde and Jenny Smith were determined to come up with a solution that retained the façade’s heritage features while ensuring the ongoing economic viability of their buildings.
Geoff and Jenny purchased the buildings in 2015 and had obtained a resource consent for redevelopment by March 2016. They had a plan to restore the exterior street fronts and extend the rear of the building, to increase the size of each first-floor apartment.
Additional pressure on strengthening timeframes
A looming deadline to strengthen unreinforced masonry buildings put extra pressure on to get work underway. Following the 2016 Hurunui/Kaikōura earthquakes, Hutt City Council issued Geoff and Jenny with a notice to secure street-facing unreinforced masonry, giving them a deadline to complete the work.
“We were well advanced with our planned redevelopment, having already completed design and obtaining a resource consent. However, the shortage of engineer resource immediately after the earthquakes, and then the deadline for completing façade and parapet strengthening, caused significant delays in completing the working drawings and starting on site,” says Geoff.
Designed by a prolific New Zealand architect
Constructed in 1926, the two neighbouring buildings were designed by prominent Wellington architect William Gray Young. He designed over 500 buildings during his career, including Wellington and Christchurch railway stations.
Geoff and Jenny were fortunate that three of the four shop fronts were almost original – providing a good base for restoring the buildings to their initial design. On the first floor, the original windows, parapets, cornices and finials also remained, but were in need of restoration and strengthening.
“These works are a significant upgrade to the current condition of the buildings. For us, restoring and reinforcing the heritage elements along Jackson and Nelson Streets was critical, guaranteeing the future of the unique heritage appeal of the Jackson Street Historic Area,” says Geoff.
New Zealand Heritage List entry - Heritage New Zealand website
Addressing structural weaknesses, designing alterations
Geoff and Jenny’s plan involved both strengthening and alteration work, so the services of a structural engineer and an architect were required.
They hired Don Thomson Consulting Engineers to identify the buildings’ critical structural weaknesses and develop a seismic strengthening solution.
The resulting upgrade solution includes:
- installing portal frames to address a lack of bracing
- installing a new roof diaphragm to increase rigidity and restrain the brick walls and parapets
- installing a concrete first floor to act as a diaphragm
- adding reinforced sprayed concrete walls to strengthen exterior brick walls
- installing steel strong backs to strengthen internal brick walls.
Architectural firm Harriot Melhuish O’Neill designed the alterations, ensuring the buildings will be upgraded to current building code and meet the requirements of tenants.
Assessing the impact on heritage
Assessing the impact of proposed works on a building’s heritage fabric is an important step in the planning process. Hutt City Council’s heritage advisor carried out an assessment of the upgrade plans as part of the resource consent.
“Our goal of restoring and repurposing the buildings was well-aligned with the principles of the Jackson Street Historic Area, and this initially made the process relatively easy. The consent conditions were also well-aligned with our intentions,” says Geoff.
“Unfortunately, an important historic building in Petone was demolished in 2017 and the public criticism that followed had an immediate impact on our project.”
“The Council and its advisors became adverse to any loss of perceived heritage value, which did make it more difficult to resolve the changes that inevitably arose as the detailed design for our project progressed.”
As the buildings are part of a listed historic area, Heritage New Zealand approval was also sought.
Heritage New Zealand supported the proposed works, saying the “key elements and aesthetics of the historic street are preserved” and the proposed additions were “intended to improve the functionality of the buildings and their long-term sustainability.”
By the end of 2017, the strengthening solution and refurbishment designs were finalised and a building consent application was submitted to the Council.
Keeping tenants informed
As well as dealing with a number of building professionals, Geoff and Jenny also had to consider their tenants.
“It was vital to keep our tenants well-informed and give sufficient notice to vacate the buildings in order for the work to start. Leases had been monthly for many years, but we gave tenants six months’ notice, reviewing the date monthly as delays occurred. As tenants vacated, we were able to complete preliminary work, such as removing floor and wall linings to test existing foundation capacity,” says Geoff.
The end is in sight
After several years of planning, and securing a $100,000 grant from Heritage EQUIP, Geoff and Jenny are delighted to have their project underway and well on the road to completion.
Preliminary works, strip-out and ground stabilisation have now been completed, with the foundations and ground floor portals ready to be installed.
“Not only are the works going to ensure public safety, the renovated retail spaces should attract more retailers and shoppers to Petone. The renovation of the apartments on the first floor and the addition of garages will also mean we can offer good quality, attractive accommodation in a central location,” says Jenny.