The day before winter solstice was a sunny one, and by midmorning the three 125-meter pipe runs on the poolhouse roof were returning 38 degree water (about 100 degrees F). But the pool overall is still a chilly 28 degrees (just a shave over eighty F). The concrete and tile sucks up an awful lot of heat. We need to add at least five degrees.
So we’re adding pipe. Each run will expand to 400 meters — 1.2 kilometers total on the roof. Painted flat black, they accumulate about fifteen degrees more than their natural baby blue color. Or maybe it’s Dusty Periwinkle.