From a climate protection perspective, promoting KFW 40 is complete nonsense. The difference in energy demand between KFW 55 and KFW 40 is marginal. What would be more important there is renovation, as significantly more effect can be achieved with considerably fewer resources.
For housing creation, of course, new construction and not renovation would be important.
Since resources are not unlimited, a decision will have to be made, and I completely agree with Nordanney that multi-story residential new construction and renovations should have priority.
Are there actually separate programs for housing cooperatives, or are they also included under the KFW programs?