Tiled roof has two semi-trapezoidal detents each packed with three corrugated water hoses acting as heat collectors

摘要

A tiled roof has a semi-trapezoidal cross-sectional profile and an overall width of e.g. 30 cm containing two such detents, their centre points being 15 cm apart. Each semi-trapezoidal detent accommodates esp. three corrugated water hoses which operate as solar heat collectors.