Faster out of the blocks

The project involved constructing two L-shaped buildings in a “69” layout with a central courtyard – one glass curtainwalled and two storeys high, the other four storeys with solid, Thin-Jointed Aircrete walls using Celcon Plus blocks 200 mm thick. The four-storey building’s original specification was dense block externally with a render finish, with the internal lining a Metsec frame system with a dry-lined, plasterboard finish. However, while the frame is quick to erect, H+H says “lead times are lengthy and overall construction time would have been slow, due to the time required to build the dense block wall for the outer leaf”.

Having successfully used Celcon blocks with Thin-Joint technology on a home extension, Balfour Beatty project manager Steve Penwill decided to deploy the system here.

A solid Aircrete wall solution negated the need for the frame, while Thin-Joint technology, using quick-setting Celfix mortar, ensured the wall was built “much quicker than a dense aggregate wall with conventional mortar”. The solid wall was finished with insulated render externally and dry-lined inside.

H+H helped develop the design, advised on acoustic solutions, and produced U-value calculations. Detailed advice on appropriate bed joint reinforcement levels reduced the amount of both reinforcement and windposts required.