To my knowledge the most used building material for most of the 1700s was wood for residential houses and stone for more important structures like churches. So in places like London, Munich, Paris, Rome, etc. how many of the privately owned or rented houses were made of wood? Was the 1700s a transitional period where other materials became used or did that not happen until later? Are there any documents or historically grounded estimates that would point to an answer? Thanks.
In the 18th century the change from primarily wooden buildings to buildings made primarily by stone and bricks had long since occurred in all the places you mention (in countries with access to timber like Norway and many Baltic countries wooden construction continued well into the 20th century).
The transition period was around the 16th century, except for in Rome, where the prevalence of Roman remains had provided enough bricks for building projects all through the Middle Ages.
In short, the premise that "the most used building material for most of the 1700s was wood for residential housed and stone for more important structures like churches" is not correct.