Iconic Chimneys Return to London Skyline - page 3 of 3
Following exhaustive surveys and testing by leading experts, it was found that any refurbishment of the existing chimneys would only ever be a short-term fix and not actually prevent the chimneys from continuing to deteriorate.
The corrosion and overall condition of the existing concrete meant restoration of the chimneys was not an option.
Recently, the latest inspection as part of the ongoing chimney programme, undertaken by independent consultancy, BuroHappold Engineering, confirmed the initial findings from earlier studies that showed clear evidence of extensive corrosion, cracking and erosion throughout the structures.
Therefore, with the agreement of Historic England and London Borough of Wandsworth, the chimneys are being dismantled and rebuilt, using the same techniques and materials, so that they will continue to dominate the skyline for generations to come.
Battersea Power Station and its chimneys form the centrepiece of the entire development; without them the development would lose its authenticity and cultural identity. These elements are central to the vision.
All four chimneys will be fully reconstructed in Summer 2016 with paint works to commence immediately after.
The dismantling process involves a circular rig slowly moving its way down the chimney from the top – with debris funnelled down a chute in the centre of the chimney.
The final element of the first chimney dismantling process required a new rig to be positioned over the last few metres of the structure, completing the internal deconstructing of the original.
Once the chimney and its surrounding brick plinth have been fully dismantled, work to rebuild the chimney begins. The rebuild process is to pour concrete into a set of wooden shutters measuring 1.22 metres in height.
The concrete section is left to set for 24 hours and then the shutters are removed.
In total, there will be approximately 70 tonnes of steel reinforcement bars that are set into the concrete in two concentric rings It will take about 6 months to fully rebuild the chimney to match the original height of 101 metres.
The entire restoration of the Power Station is costing approximately £750 m, at the end of which it will have its roof reinstated after thirty years in which it has lain open to the elements; its west wall will be rebuilt; the four chimneys will be renewed and it will be fully open to the public.
The chimneys will consist of the same materials as the originals, but with more modern steel reinforcements within the concrete to provide a more permanent solution to their conservation than simply refurbishing them. For each chimney approximately 600 tonnes of concrete will be removed and a similar volume used in the rebuild.