Due to the use of eco-friendly building materials and fitting the house with a host of renewable energies, the thermal efficiency of the house was recognized with the highest level of energetic efficiency by the Catalan institute of energy.
One drawback of building with Corten Steel is the fact that it rusts very easily and is not very resistant to environmental influences. Even the manufacturer advises against using it for architectural purposes, stating that the builders must pay special attention to the drainage of storm water to prevent staining of surrounding structures, sidewalks and other surfaces. And while the tight oxide skin of Corten Steel does reform after abrasion from snow, ice, sand, dirt and hail, it does also become thinner as it reforms and will eventually be perforated. In the case of Mint House, it might have been better to have used shipping containers after all.