Too much paint

What a nice city of Göteborg we live in! With old architecture and nice looking hipster houses!

But...

Today discovered a small crack on the wall. Need to open it to put in fibers and plaster it.. and wait a second... 5 layers of paint and 3 layers of wallpaper made the job. Water has no chance to be released from wall, in the end moist stay and start to make rost on metal beam and making damage around the park. Small crack might lead to some serious building problems.