The Seabright Street development in East London utilises H+H Celcon’s Jämerä aircrete masonry system for the whole house. It proved a resounding success, speeding construction and aiding thermal efficiency.
The terrace of three two and three-storey houses for the Bethnal Green and Victoria Park Housing Association was completed in just four months. Built by Laing Partnership, the homes have excellent thermal efficiency, with wall -Values of 0.32W/m2K.
Construction time was the subject of a comparative test, monitored by the BRE, with a similar traditionally built structure being undertaken by Laing Partnership in Edmonton, North London. Both projects were timed from ground floor level, and Jämerä was the clear winner of the contest. Despite poor weather at the start of the contract, construction of the envelope at Bethnal Green was completed in less than four weeks using a single contractor, and the follow on trades were able to make rapid progress. This was some 12 weeks ahead of the comparator at Edmonton.
The speed of construction resulted from the use of solid 355mm Celcon Solar blocks together with the quick setting qualities of Celfix mortar in conjunction with a single skin wall. The use of Celfix mortar allowed the walls to be finished internally with thin coat spray plaster, a much quicker application than conventional plaster, with a quicker drying time. External finishes comprised a combination of brick cladding system, timber cladding and a render finish. The excellent thermal properties of the aircrete wall also meant that no additional insulation was required.
Ground and intermediate floors were constructed with reinforced aircrete floor elements, aiding the speed of construction and providing exceptional thermal performance at ground floor level as well as enhanced acoustic performance at intermediate floor levels. Reinforced aircrete lintels provide thermal continuity within the wall structure, removing the problem usually associated with cold bridging. Incorporating Celcon’s reinforced aircrete elements in the roof eliminated trussed rafters and allowed the loft space to be maximised for living space.