If you include feet about sea level, Sears Tower is the tallest building in the World.
OK, maybe second tallest building in the world...unless the spires count.
What about those native huts in the highlands of Peru?
Or the tents at base camp near Mt. Everest?
Then any cabin in Leadville Colorado is about four times higher.
That can’t possibly be even close to true. It cannot even be the tallest building in the US by that measure. The Willis Tower is under 1,730 ft tall to the top of the roof antenna, and officially 1,451 ft. The highest point in Chicago is 672 ft. above sea level. Thus, even if we go by the top of the antenna and assume that the Willis Tower is located at the highest point in Chicago, the top of the building is 2,402 ft. above sea level.
The lowest point in Denver, CO has an elevation of 5,130 ft. above sea level. Therefore, ANY building located in Denver must be higher above sea level than the Willis Tower, and it’s not really even close. A 1 story house in Denver, must have a roof at least 5,140 ft. above sea level, or 2,738 ft. higher than the top of the antenna on Willis Tower, more than double the elevation of the WT antenna.