The rather unusual structure, believed to be the earliest ‘all-concrete’ constructed church, is a prominent physical and historic landmark in the area. It was built by local benefactor Lord Halifax at the outset of the First World War in the shortest possible time using the new ‘fast build’ material (then called ferroconcrete) designed to withstand local mining subsidence. The building’s roughcast finish, comprising pebbles up to 150mm, a variety of concrete mixes and textures, meant that the church was of national significance and the finished repairs needed to be sympathetic.

The new concrete was required to match the original yellow colour and its finished texture. Because of this, current concrete mix specifications were rejected, as were proprietary pre-blended materials. CRL reverted to 1960s style site mixing arrangements and it took more than 30 trial mixes to come up with the correct colour. Sourcing the various constituents also proved demanding. After breaking out some 20 cubic metres of the badly spalled concrete and reinstating it, the original exposed aggregate finish was achieved via the use of retarder-coated formwork and brushing out of the first few millimetres of soft laitence once the formwork was struck.

Supporting the church’s 200mm thick walls were 20 rectangular columns. When cut back each revealed that the reinforcement consisted only of a single 25mm diameter mild steel corner bar, without wrapping, nor continuity. Before repair, therefore, each required the installation of new reinforcement. In addition, the 19-metre high by 5-metre square bell tower was also found to be suffering major loss of section. Total demolition and rebuild was considered until CRL proposed strengthening with a 10-metre high steel frame before repair. This solution proved 60% cheaper than the demolition idea.

Other contractors claimed it was impossible to match the original finish and refused to tender for the project. CRL accepted the challenge and now it is difficult to tell the difference between the newly repaired and the old surfaces.