The German housing market is its own bird, with borrowers often having higher down payments and locking in rates for at least 10 years. The home ownership rate is just 44% compared to Spain at 83%. Because of the lack of activity, German banks traditionally value their loans when the mortgage is taken out, as opposed to other banks who more frequently update their portfolios.
New rules will force banks to revalue loans which haven't been independent assessed in over a year, essentially meaning a costly national revaluation in Germany. It is this the German bankers lobbied against and it appears they've successfully made their case.
German real estate has gotten perky over the past few years, with the Bundesbank naturally sounding warnings, but private economists note the gains have been modest by true bubble standards.