RESEARCH BACKGROUND: 'Penumbra' is a highly innovative new sort of building skin system. The invention, which extends on a design concept proposed by Richard Blythe, Paul Minifie and Jan van Schaik in a competition entry for 'The House of Fairytales', encompasses both the design and fabrication of a collection of skin cells for buildings. On 6 August 2014, RMIT filed a provisional patent application for the invention ('a building structure') with IP Australia. RESEARCH CONTRIBUTION: Penumbra's variable cells operate together as a structural enclosure and a highly articulated surface, mediating both environmental conditions and light. The 'skin' cells enable major visual and environmental effects, such as dapled lighting, shading and shadowplay. On the interior, cells can be programmed to control sunlight penetration and so simulate light filtered through a forest canopy. At night, the pixellated surface of the exeterior can form impressionistic images by controlling how much interior light is emitted. The skin cells reflect the highly specific and the universal, the interior life of a particular building and the transitions of the solar system itself. RESEARCH SIGNIFICANCE: The significance of 'Penumbra' is demonstrated by RMIT's application for a patent for this invention (filed 8 Aug 2014). The invention is not only suitable as a building façade but could be used as a freestanding partition, wall or panel, a roof or a floor structure. It is an inherently dynamic structure. Penumbra was exhibited in The Future is Here (RMIT and Design Museum London) at the Design Hub. The exhibition received wide coverage including Ray Edgar,'Evolution of the revolution',. The Age, 13 Sept 2014; Dan Rule, 'Designs for life', The Age 22 Aug 2014; Alex Newsom, 'The Future is Here', By Design, ABC Radio National, 30 Aug 2014; Fleur Watson, 'Scan made objects', The Saturday Paper, 16 Aug 2014.