When it comes to having multiple layers of shingles on a roof (rather than doing a full tear-off), what is the upside versus the downside?
Roofing Wednesdays: Beijing National Stadium
Roofing Wednesdays: La Pedrera
La Pedrera ("stone quarry") is the more popular name for Casa Milà, designed by architect Antoni Gaudí, who created a roof with sentinels to stand guard, and took six years to build (1906-1912). In 1984, it was declared a World Heritage building by UNESCO. You can even take a tour of this spectacular building!