We are talking about new buildings not old ones. In Germany currently the average sized new family house 125m2 or 1,345 sq ft. Building costs in Germany are on a par with Ireland.
Joejoe
Now we are not comparing apple with apples as its probably the same size average size in Ireland. What we are looking at is larger rural/suburbs housing.
My experience of German buildings costs is that it is much cheaper, my last house I built I basically imported it from Germany in lorries and a crew came over and built it. They basically undercut every Irish timber frame supplier by over €40k.