Building within planetary boundaries

In order to make life on Planet Earth possible, the construction industry must be completely rethought and transformed into a circular building economy. But how much new raw materials can we still use? How much residential and office space can we use? How can we replace concrete and steel? How can we dispense with building technology and still operate our buildings in a climate-neutral way? Do we need a moratorium on new construction in addition to the increasingly recognised moratorium on demolition?