COLDMILL SCHOOL, EBBW VALE, UK

To ensure the most efficient and cost-effective solution for this project, CCL was called upon to design all suspended horizontal floor slabs and supply and install its XF flat slab post-tensioning system. The company was also appointed to advise on areas open to design development. 

The Coldmill School for 11-16-year-old children forms part of the local regeneration project by Blaenau Gwent County Borough Council called ‘The Works’ The objective for the school is to develop a set of tested adaptation measures which will mitigate projected future climate change risks and ensure a standard of comfort and sustainability desired from the school.

CCL was commissioned for its post-tensioning expertise, to produce a design that would reduce costs. Savings in slab depth were achieved compared to traditional reinforced concrete slabs, with slab thicknesses varying from 250 mm to 325 mm. The CCL post-tensioned (PT) flat slabs also reduced floor to floor program cycles, produced longer spans, and maximised floor to ceiling height. The fair-faced soffits benefitted from the enhanced crack resistance of the PT slabs.

The original design included supporting corbels at movement joints. A change to the construction program required the slabs supported at the corbels to be cast prior to the supporting corbels themselves. CCL proposed the use of shear connectors to replace the corbel detail and accommodate movement which resulted in faster floor-to-floor program cycles.