China's Broad Sustainable Building Co. claims it's capable of constructing buildings faster than any other company in the world. The firm is behind the recently erected Mini Sky City in Hunan Province — a 57-story skyscraper built in just 19 days, AP reports.

The company uses a modular method of construction, which allows workers to build three stories in a single day. "With the traditional method, they have to build a skyscraper brick by brick, but with our method, we just need to assemble the blocks," company engineer Chen Xiangqian told AP.

The timeframe doesn't account for design and planning

Those 19 days don't account for concept design and planning, of course. The company spent four and a half months constructing the skyscraper's 2,736 modules before beginning the process of actually putting the pieces together. Construction of the building began last year, but bad weather stalled the project. The 19-day total is the sum of all the days spent on construction, not a single timeframe.

While such speed is impressive and the building does meet the city's safety standards, critics of modular construction — which has also been used by firms in the US and UK — say the process doesn't allow for architectural variation. Instead, boxy units are stacked together like amateur building blocks and skylines begin to look very homogenous.

The Broad Sustainable Building Co. is waiting for approval to build a 220-floor skyscraper in only three months, AP reports.