A good way to solve that problem is building a house made of wood which has no diffusion barrier and additionally putting clay on the inner walls. There are a c

A good way to solve that problem is building a house made of wood which has no diffusion barrier and additionally putting clay on the inner walls. There are a couple of interesting solutions. And the ventilation system takes care of the rest of humidity, especially after taking a shower or when cooking. The price is right too.