LOW ENERGY HOUSE IN SALEM TÜFINGEN
This was the first building when I started my own office. Inner walls made with clay and straw, thick insulation being thickest at the top like with a tea cosy, with just one tiled stove supplying all the house with warmth, a hypocaust system leading warm air around the bathtub thus making the bath the warmest of all rooms, roofed with re-used traditional plain tiles.
The heating of the house needs about 3 to 4 cubicmeters of firewood per winter (costing around 30 € per cubicmeter from the forest or 70 € when it has been already cut and dried). The solar collector and the boiler, which is positioned higher than the collector, form a thermo syphon system. The hot water from the solar panel flows through thick copper pipes upwards to the boiler, leaves its heat there and, having become heavier, flows back down to the lower end of the collector. Thus it doesn't need any pump or electronic controle. Just a refill valve, a pressure-relief valve, manometer, two thermometers showing how the system is working. Only in winter some after-heating is needed. This system has been in operation here for more than twenty years with no problems, no electricity and hardly any maintenance.