Ashley Road East, Tottenham Hale

OVERVIEW:

This project was part of a bigger redevelopment scheme awarded to Lawson Group. The site was made up of four different buildings of differing building type in a busy area of Tottenham Hale, London.

CHALLENGE

Building 1 – This was a concrete frame building with an internal floor to half of the building. It had an asbestos roof that was double-lined, this was to be removed by hand before mechanical demolition commenced. The wall panels were precast and fixed to an reinforced concrete frame.

Building 2 – A warehouse type building that had a steel frame with a plastic roof. The back wall of the building had a full height single skin brick wall.

Building 3 – This was a warehouse type building with a flat roof to the front, along with a pitched asbestos cement roof to the rear. Inside the building was a vehicle inspection pit. The walls of the building were constructed of a single skin of brick to three sides with large access doors to the front.

Building 4 – Previously known as Sentinel House, this was a former college building that consisted of three storeys. The building was constructed of a steel frame with precast concrete floor panels and there were several rooms that were divided up by stud walls. Due to the location of the building, protection scaffold would need to be installed to three sides of the building with Monarflex sheeting attached. A nesting bird survey would also be required on the top floor of this building before work could start.

SOLUTION

All services were identified in the site plans and terminated by the client. A CAT scan of the site was carried out by the Lawson Group demolition supervisor who had received the relevant cable detection training. Loose contents from within the structure, including furniture, appliances, loose waste etc. were removed by hand in a controlled manner. Door frames and skirting boards were removed by using bars and sledgehammers; all nails and fixings were removed from the walls. There was a sales centre located along Ashley Road and this was to remain in use for the duration of the works.

Buildings 1, 2 & 3 Demolition

A 360° demolition excavator with grab attachment was positioned at the rear of each structure, all voids in the ground such as manholes and sewers were protected. Asbestos roof sheets from building one and three were carefully removed by hand whilst utilising MEWPS prior to demolition. Using a hydraulic grab and sheer attachment, starting at the apex of the roof, the frame of the roof was then removed back to the first internal wall. The waste from the roof was removed by a second excavator. As each bay was removed, the side walls were lifted down using the grab attachment, any internal floors were removed as each bay was removed.

As the works progressed towards the back of each building, a banksman was positioned along the site boundary. The back walls of each building were removed using re-handling grabs. These grabs were positioned over the top of each wall where they lifted down each section of wall to ground level. All hardcore was left within the building’s footprint to enable the excavator to gain height and all general waste and wood was segregated using hydraulic grabs. This was stockpiled and loaded into the bins.

Building 4 Demolition

This was the last building to be removed so protection scaffold could be installed around the three elevations as shown to the right. No evidence of birds living in the roof was found. The excavator was positioned at the back of the building. Using a hydraulic grab and sheer attachment, and starting at the apex of the roof, the frame of the roof was removed back to the first internal wall. The waste from the roof was removed by a second excavator. As each bay was removed, the side walls and windows were lifted down using the grab attachment. Like the first three buildings, the internal floors of this building were removed and stepped back as the works progressed. The appointed scaffolders were onsite during the removal of the building so as each bay was removed, the protection scaffold could have its sheeting removed back to each column. As the mechanical deconstruction of each building progressed, the dust boss was moved along ensuring all areas were covered and no dust was being generated. Once all the waste had been processed and removed from each building, the slab was cleaned off using a grading bucket. All slab and foundations were removed, processed and removed from site. Once the slab and foundations had been removed, the reduce dig to a depth of 500mm commenced. Starting at the back of the site, the soil was dug out and loaded into eight-wheel lorries for removal from site. All edges of the excavation were battered back to 45° around the boundary of the site and levels were checked by the appointed engineer once the soil had been removed.

The site boundary hoarding was removed in sections, crushed concrete was then imported and placed around the site boundary to a depth of 500mm and approximately 1000mm wide. Site hoarding was then moved back on top of the crushed material.

RESULT

All four buildings were successfully and safely removed from the site and handed back to the client on time for the next stage of the redevelopment.

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.