Timber framed building with various structural problems. Planning permission conditional on the retention of architecturally significant Grade I listed chimney, incorporating baker's oven. Chimney was unstable and required stabilising to prevent its collapse during underpinning work.
To install grouted rigid steel bars at the bottom of the chimney only. Required 50mm diameter holes. Likely to further destabilise the chimney and was rejected by the engineers.
The complete chimey was stabilised using concealed stress-free stainless HeliBars grouted right around the chimney at regular intervals to create masonry ring beams. CemTies were used to stitch the weak masonry. A major catastrophe avoided. Being behind schedule, the main contractor decided to excavate two of the chimney's underpinning pads in one sequence. The central 1.8m section of masonry collapsed, but only up to one course below the bottom HeliBar. Due to the unique nature of the installed Helibeam System the masonry was sufficiently reinforced to span the void between the outer piers, preventing any movement of the upper structure. A structurally and financially disastrous situation was avoided.