May 19 2008
H+H aircrete products are making a major contribution to Barratt’s highly successful Green House at the Building Research Establishment’s Innovation Park near Watford, a showcase of innovative construction methods offering practical and affordable sustainability.
The Barratt Green House, winner of the Mail on Sunday’s 2007 British Homes Awards Design competition for The Home for the Future, is the first home built by a volume housebuilder to achieve Level 6 of the Code for Sustainable Homes.
The shell of the three-storey Barratt Green House has been built by H+H UK recommended contractor Minett Group using storey-height aircrete panels 600mm wide and 200mm thick, together with Jumbo Units, all ‘glued’ together with Celfix thin joint mortar for rapid construction.
Storey-height aircrete panels are widely used in Scandinavia but are not yet marketed in the UK. The excellent insulation they provide is a result of aircrete’s aerated structure comprising thousands of tiny bubbles, with thin-layer mortar joints reducing thermal bridging. The solid aircrete walls, which assisted the Barratt Green House in achieving extremely low air permeability levels, resulted in an A rating under the BRE Green Guide and a U-value significantly better than 0.15W/m2K. They were externally lined with insulation before receiving a render finish. Internally the walls will be dry-lined with services run in the void between the wall and the plasterboard. A positive decision was made to use aircrete with concrete floor slabs within the thermal envelope to provide high thermal mass which mitigates the peaks and troughs of temperature change within the home.
Unlike other houses on the site the Barratt Green House is conventional in appearance and the company intends it should be the subject of rigorous scientific testing over a two-year period to assess every aspect of the design, construction and materials. Ultimately Barratt plans to take the most successful aspects of the design and apply them to homes that it builds.