Imagine a vegetable in a plastic bag vs a vegetable in a bamboo box. The one in the plastic bag rots while the one in the bamboo basket grows old and withers. In technical terms, Natural buildings are breathable and healthy. 

The cost of a natural building varies from each site depending on what resources you have, how you are going to do the building(are you going to build yourself?/ are you outsourcing it?), what kind of finish you want, etc. It varies greatly from place to place and from person to person.

When designed well, natural buildings can last for generations as has been proven by our heritage in traditional homes. Design principles like a good hat and a good shoe keeps your building safe. Giving a good plinth and a good roof is one of the principles rules in designing your natural home.

Natural buildings can be low cost only if you are ready to put in the effort and be involved in the building hands on yourselves. Natural materials on a large part are low cost. 60-70% of the cost is towards labour. In comparison, a normal building has materials that are expensive. But if we look more closely, many materials like cement and steel are at subsidized costs in the industry. Hence, we are unable to compete cost wise. Also large scale manufacturing is not possible in natural building.

Yes, natural buildings require maintenance. Natural homes are living, breathing entities that are no different from us. If we take care of them, then they will take care of us. Lime paint every year for lime plasters, oiling for the wood are some examples of the maintenances that are required in a natural home.