It is only a matter of time, to construct everything by robots... Construction will be just another information technology soon. We will only need the knowledge, and things will get built. The reason of constructing a building is more difficult than constructing a car is that it entails much more real life variables in uncontrolled environments, but this will not stop the automation process in the long run. Sooner or later, just like autos, all our buildings will also be built by machines. Here is a good example: