As human beings, we seem naturally drawn to the tops of things. Have you ever heard a friend boast of visiting the ground floor of the Empire State Building? It’s surprising, then, how few houses offer access to the prime real estate up overhead, because sitting on a roof can feel like sitting on top of the world. And considering how little it takes to make a roof habitable, a deck up top may deliver the biggest bang for the buck in residential construction. After assembling this collection, we’re inclined to view any roof one can’t furnish with a table and chairs as an opportunity missed.