KfW-Denkmal
The German efficiency house class for a listed building, where full insulation is not permitted.
The listed building class applies where heritage protection prevents the measures the ordinary classes require, chiefly external insulation and window replacement.
Its requirements are correspondingly lower and are set against what the building allows rather than against a fixed percentage, so it is not comparable with the numbered classes.
It exists so that a protected building can still qualify for subsidised financing.




