As part of a refurbishment and restoration programme at the world famous Alexandra Palace, special Helifix repairs were devised to strengthen an arch window and two adjacent minor arches on the north-west tower, after historic movement of this Grade II listed building had affected the support piers.
The Helifix engineered design permanently tied the three arches together, addressing both structural and aesthetic requirements, enabling previously added brick and steelwork to be removed and the original window opening to be reinstated.
A combination of Helifix masonry repair products and concealed installation techniques were used. HeliBars were bonded into the mortar beds above the arches to reinforce the masonry, create deep masonry beams and spread the structural loads. Fully grouted CemTies were installed up through the arches to secure them to the masonry and support the lintel loads. Once the HeliBars and CemTies had been installed the infill brickwork and steel beam were removed.
Careful alignment of two 7m long SockFix bars ensured that they would be virtually hidden when viewed from ground level. Once the repairs were completed, the historic arches were reinstated, the original window frames retained and the tower’s aesthetics and original materials were preserved.
For project-specific technical advice about the use of Helifix concealed structural repair products and techniques contact the Helifix team on 020 8735 5200. Alternatively you can find product information, relevant literature and a wide range of case studies online.