In our previous articles, we have cautioned that an energy retrofit should be approached with an integrated, whole-building approach, and by a professional with experience in calculating and simulating thermal envelopes. The photos below show what happened to one family’s home when they decided to do an independent partial energy retrofit, without consulting a qualified professional. In this case, they decided to replace the old windows of their house with newer, high performance windows, hoping that they would be able to reduce their energy consumption.