The KfW Efficiency House classifies new construction and retrofitted buildings according to primary energy demand relative to the reference building: KfW-55 = 55 %, KfW-40 = 40 %, KfW-40 EE (renewable energies), KfW-40 NH (sustainability).
Currently eligible for funding: KfW-40 and KfW-40-NH via the BEG programs. Retrofitting: KfW-55 and KfW-70.