The image above shows the level of detail we go to in terms of sustainability. The roof was clad in salvaged natural slate, which is not only extremely sustainable as a material, it is also naturally weathered and beautiful. The groves in the timber show the outer edge of the window frame before it was fitted. It is a passive certified window frame, but uses only air as the insulate in the frame by an ingenious design of a series of groves and voids. This avoids chemical based insulates that are often used. More detail of the project can be seen in the latest issue of Passive House Plus: www.passivehouseplus.ie.