In contrast to the passive house movement, where houses become plastic bags, dead, with petroleum-based materials, regulating air only with expensive ventilation systems, natural building principles apply the philosophy of active buildings with natural and thus ‘living’ materials. Aside from the ecological dimension of the story, designing buildings with natural material simplify joints and details, bringing some logic into the principles of building.
One of the main problems we have to deal with is the problem of ventilation and the balancing of moisture inside our newly insulated houses. Why is this a problem? Put a plastic bag over your head and try to breathe. If we want to live in our buildings, the materials need to breathe. In other words, they need to regulate vapor naturally.
With this very simple principle, there is no more confusion about the exact placement of foils and plastics because there are none. The mixture of hemp and lime can therefore be used as insulation on the outside of an existing wall, as well as on the inside.
It is a self-sustaining material, but cannot carry loads like beams or cabinets. It is not a structural material, as it only supports itself. Due to its own weight, it should be placed on foundations.