Darby House, Swindon

OVERVIEW:

Lawson Group would be responsible for the demolition and asbestos removal of the former multi-storey concrete framed office block.

CHALLENGE

Extensive removal of Asbestos Insulation Board (AIB) boxing, cladding, heating panels, soffits, external soffits and fascias would be required. The office block was located adjacent to a busy town centre road so health, safety and environmental factors would need to be considered.

SOLUTION

A strategic methodology was put in place to ensure that all safety precautions had been met. Working in a tight vicinity close to a pavement, road and other businesses emphasised the importance of planning the works.

An asbestos removal programme of ten weeks was implemented for the licensed removal works. Twelve operatives were appointed to complete the works in conjunction with a bespoke plan of works that had been prepared. Scaffolding was erected to the full external perimeter of the building, this enabled a working platform and formed a frame for asbestos enclosures around the external soffits and fascias. These were lined and secured with polythene to form the external asbestos enclosures. Several enclosures were also formed internally to remove the AIB boxing, packers, floor tiles and lagging.

First and second floor areas were serviced and accessed via a HAKI staircase with bag and airlocks positioned on the scaffold platforms. Waste and transit routes from upper floors were also via a HAKI staircase. This transit route was an exclusion zone and access was prohibited for any other site operations. An enclosure was formed to remove the AIB boxing to service ducts, cladding to steel beams and columns, fire breaks and panels above and below windows.

For the external works, two operatives worked together in each enclosure during the removal process. The bead holding in the panel was carefully removed using small hand tools, an H-type vacuum was used to prevent fibre release. The panels were then removed by hand, shadow vacuuming and spray suppression w as carried out by the second operative throughout the process. The panels were mmediately double wrapped in 1000-gauge polythene sheeting. Once all panels had been removed, they were transported to a waiting hazardous waste skip.

This process was repeated floor by floor until all external fascias had been removed and the building was clear o asbestos ready for demolition. The office block was linked to a large industrial distribution warehouse, a hand separation area was formed using MEWPs and hand tools, this area remained protected by scaffolding during demolition works.

Lawson Group’s own Liebherr 954 was used with a multiprocessor shear attachment to demolish the remaining structure. Works then commenced at the Eastern elevation.

Using the demolition equipment, the roof was removed back to the first supporting column, allowing one bay of the roof to be lowered carefully to the second-floor slab. The debris from this was then scraped back, allowing this to fall into the drop zone – to ground level. This process was repeated to the first and second floors and the sequence continued throughout the remaining structure. Dust suppression was maintained throughout the works by means of a Dustboss.

RESULT

The buildings were demolished in their entirety,  including removal of ground floor slab, foundations to the footprint of the buildings and surrounding hard standings. All waste was segregated for recycling and the concrete and bricks were crushed and reused onsite.

To find out more on how Lawson Group can help with your next demolition or asbestos removal project, call 01793 782000, email enquiries@lawsongroup.co.uk.