There is a huge construction project in Shanghai with goals to add a roof to the old residential buildings. It is called 平改坡 (or roof to slope) project.
In the 1980s, a certain type of residential buildings were built widely all around China. Below is the picture of this type of houses in Changsha in central China. These houses don’t have a sloping roof and look bad.

© Jian Shuo Wang. Ugly houses in Changsha
Unfortunately, most of the houses built in 1980s and early 1990s are the same, which were called matchbox houses.
The good news is, Shanghai government has working very hard to remodel the houses by adding a roofs to them. Below is a picture I took from the top of the Metro Tower. The red roofs of the houses were added in the recent two years.

© Jian Shuo Wang. Houses with roofs in Xujiahui
Working Vertically
Below are the scene of the construction of adding the roof. The house was surrounded by the temp frames so workers can pain the house and add the roof. I took some pictures of the interesting scene. Many works line up vertically along the wall of the house and transfer building materials from top of the house down to the ground, hand by hand.

© Jian Shuo Wang. Workers line up vertically to transfer the building materials down to ground

© Jian Shuo Wang.
It was so funny.