There are many reasons why people might want to retrofit their homes, but saving money isn’t one of them. After grants, a deep retrofit costs roughly €16,400 for an apartment, delivering about €700 annually in energy savings. For a detached house, your deep retrofit spend of €42,900 will likely deliver only about €900 a year in energy savings, so 48 years to break even. But saving money? The Oracle of Omaha would surely see a deep retrofit as an even greater financial folly, one that heats the house while freezing the finances.
