Hello,
A pretty fragmented story seems to be emerging. There is another conceptual model that might be useful though not really widely grasped yet especially among architects and that is a systems approach. Instead of looking at individual components in isolation, site, frame, infill, roofing, sealing, insulating, heating, air quality... why not look at how all these things interact more intensively. I mean to say, it is really getting back to a rational approach.
We imagine wanting to improve on shortfalls of the way a half timbered frame has evolved and begin with the interface between the frame and infill where those openings develop and supposedly let the air in. So we seal everything up. It is the cause of two main unintended effects. A moisture build up and retention within the frame and reduced air circulation inside. Not only is the inside climate negatively impacted but the seeds of self destruction are planted within the very core of the building. I think the second law of thermodynamics is doing fine without any extra help, thanks.
What about an appropriately integrated shell of timber and say clay brick, for example - only because this is in between the two extremes of kiln fired brick and wattle and daub - which can be permeable on all counts, it will not seal the inside off so there will be a constant and desirable exchange leading to more efficient warming of the inside air - trapped motionless air constantly takes on and holds moisture becoming harder to warm - through a centrally located radiant heat source, the thermal mass of the walls will even out seasonal fluctuations of temperature and humidity for example as it regulates or maintains the ambient room temperature. The ambient temperature is what is important because it is what people in the room experience. The ambient temperature is the average temperature of all the combined exposed surfaces of the space. A final influential factor is the micro environment where the building is situated which can be planned appropriately. You see how it becomes difficult then to think about the infill only.

Greetings,

Don Wagstaff