From Concrete to Wood in Building: Combatting Climate Change
Keskiviikko 18.12.2019 klo 14:53 - Mikko Nikinmaa
Another indication of the climate change is the observation that Australia experienced the hottest day ever. Despite this and a multitude of other signs, the backward-looking politicians like the Australian prime minister thwart any actions to combat climate change. President Trump lists as one of his major achievements “cancellation of the unfair and costly Paris Climate Agreement”.
The discussion about climate change has concentrated on coal and oil use in energy production and on eating meat. Also flying and rain forests have attracted much media attention. It is seldom mentioned that the size of the human population is a problem, and actually makes the populistic solution of going back to the past impossible. In the past that the backward-looking leaders want to return to, there were two-three billion people, now we are about eight billion. With two-three billion people, limits to growth had not been reached, now they have. The importance of unicellular algae of the ocean in generating the oxygen balance by photosynthesis is often not acknowledged. Yet, almost half of the oxygen-generating photosynthesis is carried out by these small algae. Finally, one of the important carbon dioxide sources is concrete building – it accounts close to ten percent of the present carbon dioxide emissions.
Thus, one should stop building using concrete and steel. Most of the carbon dioxide emissions are due to cement production, an indispensable component of concrete. Making brick or stone houses would already be much better than concrete. However, the pest alternative would be wooden houses. Technologies are already available, which enable building multi-store houses. Further, the probability of burning of wooden houses is much reduced from 19th century, when whole cities could burn. In a wooden house the carbon would be stored for its entire life length, up to several hundred years. Thus, if all new buildings were wood-based, the carbon footprint of building sector would decrease for 10 % of world total to 0. This would be a huge win in combatting climate change, and could be reached with the presently available techniques. In view of this, one must ask: why is it not done?