Precision demolition on a heritage building in New South Wales
A three storey solid brick heritage building at Trinity College in Lismore New South Wales demanded significant asbestos removal and demolition works ready for re-use.
To prepare the building, heritage archival records were removed and stored, before completing a full internal strip out. Existing stairways were also deconstructed for later reinstallation.
Demolition
Excavation and external demolition works then began, including a solid brick retaining wall and footing, and chimney stack.
At various stages of the project, the sensitivity of the site presented several changes to the scope of works. Additional asbestos was found upon opening the ceilings and lifting existing floor coverings.
The building had also undergone various design changes over the years and investigation work revealed that certain walls were load bearing but earmarked for removal, so structural support had to be installed prior to deconstruction.
The existing lift was decommissioned prior to McMahon Services arriving on site, making it physically challenging to haul the masonry from the upper level walls to the ground floor for removal, with demolition works required on four different levels of the building.
Improvising on site, the project team constructed a purpose-built scaffold tower adjacent to the bin located on the first floor and chuted the material straight in.
The removal of the lath and plaster ceilings created tremendous amounts of dust. It was imperative to contain the dust inside the building due to the neighbouring college and Cathedral, so each room was sealed individually without the use of water to avoid damage to the floors and ceilings and lower levels, which had to remain in place.
The project team was also confronted with inclement weather conditions, with flooding from the Wilsons River located only 300 metres away.
Despite the complexities of the 12 week project, McMahon Services delivered a seamless demolition, working carefully under strict supervision.
