Channel 4's 'Grand Designs' featured Helifix masonry repair techniques being used to retain a 300 year old dilapidated stone barn during the development of Hill Barn/Underhill House. Although constructed on a hill top site in an Area of Outstanding Natural Beauty, the project received planning consent because the this strikingly modern house was built below ground level and is invisible from the surrounding countryside. A principal condition of the planning permission was that the ancient stone barn on the site must be structurally repaired and retained and supported by a steel frame while the ground beneath it was excavated for the new home. When the project was completed, the barn was the only visible structure above ground level, becoming a new office for the owner and architect of Underhill House.
Built with rubble-filled Cotswold Stone walls, some 600mm thick, the unstable barn needed to be consolidated and strengthened to protect it during construction of the new subterranean house. A scheme to reinstate its structural integrity was designed by Helifix engineers and undertaken by the local Approved Installer.
The completed property is the first to be registered in England designed to Passivhaus standards and it's very high insulation levels will result in 90% lower carbon emissions than normal.