KKB Demolition were appointed as principal contractors to deliver the enabling works for the development of a retail site in Chatham. The location, which was formerly occupied by Go-Outdoors and Tesco, is being redeveloped into housing comprising 319 one, two, and three-bedroom flats, new public spaces including a central plaza, nature play area, and landscaping as well as plans to refurbish and reopen its adjacent multi-storey car park.
Management of sensitive receptors was a key consideration as the site is situated adjacent to residential buildings, a dual carriageway and the town’s main retail district, The Brook. Planning was fundamental to this development with footpath and bus stop closures needing to be approved by the Local Authority. We circulated newsletters to the local community throughout the 9-month project to keep them updated with progress. The site was established and secured by installing over 350 metres of solid hoardings. A specialist contractor was employed to disconnect and cap-off services to the site including water, electricity and gas.
We also instructed an independent structural engineer to undertake an evaluation of the stability of the adjacent multistorey car park once the main building had been demolished. Their recommendations included a temporary works system involved back propping of the existing retaining wall which was installed by an engineering subcontractor. The GoOutdoors building was fully scaffolded and clad in monoflex to contain debris and dust during demolition.
We then instructed our licensed asbestos contractor to remove all licensed and non-licensed asbestos-contaminated materials including AIB boards, gaskets and floor tiles. Following this our in-house team undertook strip-out which involved removal of all non-structural items from the buildings including doors, frames, false ceilings/floors, partition walls and M&E installations. Due to the large open-plan rooms, we used a skid steer and small 5-to-8-tonne excavators to minimise the manual handling and work-at-height risks involved. Working concurrently we commenced the structural demolition of the former market hall which comprised a steel-framed roof tied into concrete legs with a small retaining wall. This was undertaken using a 20-tonne excavator with shear and grab attachments. A hydraulic breaker and muncher was employed to tackle the retaining wall.
Larger excavators (40-tonne and 50-tonne) were required to demolish the main building which was constructed of reinforce concrete with rebar over an inch thick in places. The sequence followed the structural engineer’s drawings, leaving two bays up around the perimeter which had to be carefully taken down using a 32-metre high-reach excavator. The scaffold was progressively struck during demolition. Once the building was down to a safe level smaller machines were used to take it down to the ground floor slab. Careful sequencing and planning of the various disciplines ensured continuous structural demolition to minimise programme.
The demolition generated over 40,000 tonnes of concrete/hardcore arisings which we processed on site using mobile crushing/screening plant to produce 6F5 aggregate which was left on-site for use as a piling rig and for fill purposes. All other waste streams were segregated on-site and collected into skips for removal to a local Waste Transfer Station in Gillingham. This resulted in 95.8% of all wastes from the project being re-used or recycled with just asbestos-contaminated material being disposed at landfill.
Close proximity to residential buildings and the main road required us to employ methods to minimise emissions of dust, noise and vibration to acceptable standards. Three large ‘dust fighter’ water-spray machines were used continuously to damp-down the works. Noise monitoring using hand-held censors was carried out three times a day at six locations inside and outside the site’s perimeter. An environmental engineer undertook vibration monitoring involving censor targets placed on the main building’s wall facing the multi-storey car park.
Testimonials
We were very impressed with KKB’s professionalism and attention-to-detail throughout this multi-disciplined enabling works project. Their management team were able to plan, sequence and micro-manage the works to meet a challenging programme and methods to minimise pollution and disruption streamlined our interface with the local community