A bird's-eye view of a residential area in Yunyan district of Guiyang, Guizhou province. The blue tin roofs can be seen on almost all buildings, making the area look like some shantytowns. Residents said they built attics to store things and to keep rain from leaking into their homes. Cheng Wen / for China Daily

Each residential building in the area is topped with an attic built with blue tin. A bird's-eye view gives a misleading impression that this might be a shantytown.

But that's not the case.

A resident surnamed Li living on the top floor of a building in the Dongshan community of Yunyan district explains, "Our roof always leaked, especially in the summer when it rains often, so we built an attic on top of the building."

Li said his family built the 40-square-meter blue tin-roofed attic a year ago at a cost of 40,000 yuan ($6,416).

"It's cheap, easy to construct and more importantly, it works. Many neighbors have built them, so did we, too," Li said.

"Inside (the attic), the ventilation is bad, but we don't live in there. We use it as a storehouse."

Realizing the practical use of such attics, many residents have joined in, according to Chen, another resident in Li's community.

Chen, who does not live on the top floor, also managed to build one on his balcony, which covers 5 square meters, for "piling up sundries", she said.

However, He Guo, an official of the Yunyan urban management team, said such attics, practical as they might be, pose potential security risks. For example, on days when the wind is strong, the structures could blow apart as most do not meet normal construction standards.

Yet, demolition of such attics has proved difficult, he said.

He also explained that many of the blue tin attics are in low-income suburban areas where people cannot afford bigger homes to accommodate their growing families, so they are keen to expand their current houses.

"Our main objective is to target those who make a profit illegally from building such temporary rooms. So far this year, we have demolished 242 such rooms in Yunyan district, with an area of more than 30,000 square meters", He added.

Zeng Jun and Jia Tingting contributed to this story.

Contact the writer at lijun@chinadaily.com.cn