Sales & Technical: +44 (0)20 8735 5200 | ROI: +353 (01) 695 0726 | [email protected]

Sympathetic repairs stabilise granite lintels

Client:	Bon Accord Free Church
Location:	Aberdeen, Scotland
Engineers:	Fairhurst
Approved Installer:	Corecut
Reference No:	CS198

Built in 1845 entirely from local granite, this church had suffered from historic settlement which had resulted in shear cracking in the major granite lintel above the main entrance and in several of the window lintels.

To retain the aesthetic appearance of the building a discrete and reliable method of securing the lintels was required that would stabilise the masonry and prevent future cracking. The alternative would be the disruptive and expensive removal and replacement of the granite lintels.

The Helifix Solution

Structural repairs were devised, using Helifix remedial products and concealed installation techniques, which would reinforce the masonry above the affected lintels, ease the structural loads and restore integrity.

Above the windows, pairs of stainless steel HeliBars were bonded, using HeliBond cementitious grout into channelled-out mortar beds at two levels. These provided lateral restraint, stitched cracks and created masonry beams, using the existing granite, which spread the structural loads.

To provide a more robust solution over the main entrance, two SockFix grouted sock anchors were installed. Two clearance holes were diamond core-drilled, 100mm apart and passing through the lintel, almost the full width of the tower. The anchors were then inserted and pumped full of grout, filling any voids and forming a strong mechanical connection with the surrounding masonry. Retained cores were then replaced to create an almost invisble repair.

All cracks were filled with CrackBond TE non-shrink thixotropic epoxy resin. The resin filled the cracks and formed an excellend structural bond with the masonry.

All the cost-effective concealed repairs were completed quickly and efficiently and, after making good, there was virtually no sign of the works that had been carried out.