Bromyard House was a 1960s tower block in Peckham, London, with 56 dwellings over 14 floors. It was built using a technique known as ‘Large Panel System’ (LPS), with some additional bracing undertaken later.
However, a structural assessment of Bromyard House and three adjacent tower blocks in 2017 recommended that Southwark Council should either strengthen the blocks or demolish them as soon as practicable, because they did not comply with guidelines for LPS construction.
The Council engaged Colemans to undertake the works at Bromyard House, which was the first of the four tower blocks to be demolished, making way for new housing on the same site.
Using our experience of deconstruction and demolition of high rise residential buildings, our team developed a Method Statement to set out the works.
Our plan consisted of removing roof area structures and upper floors in de-build sequence, using a specialist tracked crawler lifting crane to assist on the movement of the LPS structure. We then deconstructed to a suitable height, from which 50-tonne demolition excavators continued down to ground.
This complex deconstruction required significant engineering and planning, to ensure a safe and successful result. Push pull propping was installed at each level to allow step-down demolition, with plant operating from the slab below the one it was demolishing.
The LPS structure meant that all walls and floors were made of huge individual concrete panels.
When Bromyard House was built, these panels were built in a factory and delivered to site ‘flat packed’ on lorries. They were then lifted into place and connected together to make the overall building structure. The wall panels measured 2.7m tall, which is the height of one storey, with floor panels 2.7m wide and between 2.7m and 5.4m long.
The safe removal of these panels was key to the success of this project. Once roof coverings and insulation were removed, our team set about breaking out lifting eyes within each floor panel that made up the roof, before removing grouting cement and fixing each panel to the crane individually.
Once fixed, operatives could flame cut all connections so that the panel could be safely lowered to the ground. The same method was used for the wall panels, removing props at each stage as the deconstruction progressed.
This process was then repeated for each floor until the fifth floor, for which excavators could be used from the ground.
Once each panel was safely lowered to the floor and unchained from the chain block, our team used a 20-ton excavator equipped with a static muncher to process them.
This consisted of the machine munching each panel to reduce the size and remove re-bar, so they could be removed from site. A mobile crusher was used to crush slabs into a 6F2 grade aggregate for reuse.
Colemans also removed all foundations and flattened the site ready for construction, using material generated from crushing operations to level the site off, in line with our continued commitment to reuse materials wherever possible.