The natural stone facades are not only better from the environmental point of view, are also much more profitable as far as costs are concerned. For example, the heat transfer coefficient of a natural stone facade is 0.32 W/m2, well below a glass facade, which is 1.25 W/m2. Due to lower thermal conductivity, the heating needs of buildings with natural stone facade are considerably lower. Moreover, the negative economic and ecological effects of the glass facades due to heat loss in winter and the amount of air conditioning needed to cool the building in summer have not been taken into account when conducting this study.

Finally, not least, the construction of natural stone facades is considerably more cost effective than glass facades. After studying 20 facades, the Bavarian Supreme Court of Audit concluded that the investment costs are proportional to the amount of glass used in construction. While the facades pierced with a glass content of 35% required an investment of 400 € / m2, the facades of glass containing 90% need € 1,280 / m2. Each percentage of glass content added to the amount required by the usual perforated facade gets 16 € / m2, including their costs. (Construction index November 2006). Also, the maintenance costs of natural stone facades are half the cost of maintaining a facade of glass. In addition, the annual cleaning of glass surfaces adds another 1.5 € / m2 on average. More specifically, the cleaning of the perforated facades costs 1 € / m2 and that of regular glass facades 4 € / m2. The twin buildings with facades made of glass and building materials requiring intensive cleaning or having a difficult access cleaning costs are higher.