And it's good for the planet, too: the trees absorbed carbon when they were growing up, and they gave off oxygen, and now that carbon is trapped inside the walls and it's not being released into the atmosphere.
Fa anche bene al pianeta: gli alberi assorbono l'anidride carbonica mentre crescono e rilasciano ossigeno, e ora l'anidride è intrappolata nelle mura e non verrà liberata nell'atmosfera.