Construction contractor Icon Group is conducting bulk earthworks and demolitions in the Johannesburg central business district as part of a construction project aimed at developing a new Title Deeds Office for the City of Johannesburg.
The project, a partnership between the city and the Department of Public Works and Infrastructure (DPWI), is aimed at revitalising the city’s Title Deeds Office so that it can cope better with its administrative load and is better equipped for future growth in the property development and infrastructure sector.
The project value for Icon Group’s scope of work amounts to about R20-million.
Work started in October, with Icon Group MD Wayne Neary expecting the company’s scope of work to be completed by June this year.
The overall project is expected to continue for about three years, with two other contractors responsible for the lateral support infrastructure and the construction of the new building respectively.
The project is centred around a 120-year-old heritage building, which needs to be preserved, thereby increasing the complexity of the work. The heritage building will require renovation and rejuvenation so that it can be integrated into the new multistorey building, which will be constructed directly behind it.
Neary explains that the heritage building has structurally unsound walls and deteriorating brickwork. Consequently, the refurbishment of these walls required careful hand demolition so that about 25 000 original bricks could be preserved, cleaned and reused in the building’s reconstruction.
For the safe hand demolition of the ageing brick walls, Icon Group brought a number of cherry pickers to site so that the workers could demolish the walls from the top down, thereby avoiding any potential collapse.
In addition to the heritage building, three old, dilapidated houses at the back of the site had to be cleaned out first and demolished to make way for the excavation of a 15-m-deep, five-storey basement.
These houses were demolished using traditional heavy demolition machinery, including grabbers, heavy duty saw blades, hammers, track machines and pulverisers.
“It is a major challenge to dig a 15 m basement right next to the heritage building. Although the building has been stabilised, the ground conditions are somewhat unknown and we have to improvise and think on our feet,” Neary says.
He adds that the rainy season has added another dimension to the challenge, causing the flooding of pits, muddy conditions and potential ground instability. Various measures have been put in place to mitigate the impact of rain on the site.
“The speed at which we can excavate the basement is governed by how quickly the lateral support contractor can complete the lateral support. This will include applying gunite on the walls to support the excavation,” he explains.
All demolished material and removed earth are trucked off site to Icon Group’s materials processing lot, where it is recycled into aggregate and used at other sites.
The excavations for the basement started this month, with about 40 Icon Group personnel on site at the project’s peak, along with a 40 t and a 50 t excavator, a tractor loader backhoe and about 20 haulage trucks.
With so many trucks entering and exiting the site daily, Neary says managing traffic in such a busy part of the city is a challenge; however, the company has plans in place, in cooperation with the City of Johannesburg, to mitigate these challenges.
Meanwhile, Neary says the decision to centre the project around the dilapidated heritage building was a “smart move”, since the DPWI already owned the property, thereby allowing for simultaneous urban revitalisation and heritage preservation while minimising costs.
The project is also aimed at achieving a Green Star rating, which is an independent verification of the project’s sustainability through the Green Building Council South Africa (GBCSA).
The certification process is managed by the GBCSA internally using a case manager and externally using appointed assessors and moderators. Each certification is subject to these independent third-party individuals who provide transparent feedback for the case manager and project team or accredited professional.
Neary says this project signals a good start to the year, which he believes will deliver more development, as projects that were postponed last year, owing to Covid-19, now come on stream.