Casa Cusau was designed by Architect owner Marc Furnival as his own house, and completed in 2012. It is on the site of a derelict stone barn, ‘Cusau’ being the historic name.


The underlying design concept was developed to make the interior and exterior complementary yet distinct: mostly traditional in appearance on the outside but with some contemporary aspects, and mostly contemporary inside with some traditional aspects. The traditional aspects were to achieve a sense of connection with the surrounding, and also as a contrast; a foil for the generally contemporary nature of the house.

Design context

On the premise that good design is about interpretation, a study was done which allowed a contemporary reading of the local context for a scheme that is fit for purpose and not a pastiche or sentimental intervention. One aspect of the research began with an analysis of the vernacular house to highlight: key architectonic elements, proportions, colours, materials, details, and the overall combination and balance of these.


The house used local materials as far as possible. ‘Local’ is taken to mean materials sourced from within an hours drive and including labour that lives or substantially works in the area, as well as details that use skills that are inherent to that area. Although some items were brought from much further, for example, the windows are Technal and came from Germany.


The wall construction consists of: limestone 8cm, clay block 29cm, insulation 6cm, brick 7cm, lime plaster 2cm. This achieves an overall U-value of only 0.3. The internal walls are finished in a natural lime plaster, which has a varied grey tone, and is a breathable material.

The heating system is air source heat pump/ aero-thermal (as opposed to geo-thermal), with underfloor heating. The exposed concrete floor is not just concrete but includes anhydrite as the main mass, a locally sourced mineral by-product with much higher conductivity than normal cement and is more flexible, so does not tend to crack.


The house appears as a case study in an article on sustainable development, as part of a wider discussion on semi-rural regeneration and design process as a representation of the underlying organisational framework of human activities which, through considering the nature and implications of those activities, forms a basis for a re-ordering of design rational and re-establishing of the wider relationship between activity, function and building.

‘On human activity and design – Towards more sustainable development’, Reinventing Architecture and Interiors – a socio-political view on building adaptation. Editor Libri Publishers: London. ISBN 978-1-907471-73-5.

On human activity and design – article. How re-thinking design and human activity could help reinvigorate the rural economy. Marc Furnival, Architect & Urban Designer