If you have ever been faced with construction or renovation here then you are familiar with the nightmares. Most Chinese workers are full of goodwill but have no clue what they are doing. They are badly paid and training is non-existent. So no surprise if your nice walls crack after a couple of months, the plaster comes down from the ceiling after one year and the walls have zero insulation.
My father was a real expert mason and bricklayer and he would have a heart attack (translation: he would curse like a bricklayer does in my country) seeing the miserable quality of work.
See here a typical example of a “Chinese wall”.

I argued with the bricklayers who gave the silly explanation that it was the right way to do, so when later covering the wall on the mortar would stick better. Go tell that somebody else, not to Gilbert the son of a real mason. It is just the contrary, you have to put excess mortar between bricks and scrape the excess off. If the mortar does not adhere to the wall it is because the mortar is of the wrong mixture – and you have to first wet the wall. Doing it the Flemish way you can’t get the mortar off later on.
So, if you wonder why you can hear your neighbor snore or the wall is so cold in winter that condensation dissolves the “plaster” and you can harvest mushrooms, don’t be surprised. Of course most “specialists” have no clue how to (correctly) make an insulating wall.
What China needs are more vocational schools and more respect for its workers. And pay them better. Then you’ll avoid the every-two-years-needed repairs.
My wife still hasn’t gotten the message. Maybe she needs vocational school too. She argues (Chinese wife style, does that sound familiar to you?) well “that’s China”.
Funny people some Chinese. A Mercedes has to be perfect and cannot break down. But Chinese construction is by definition poor. Way to go.