When you start to dissect how buildings work it is really complicated. A right old mix of elements like:
Thermal loss of materials
Air change requirements for different rooms / activities
Acoustic characteristics of materials and structures
Noise generation and levels
Lighting, natural, artificial, reflected…
This doesn’t even start to take into effect the human elements of knowledge, behaviour etc.
Modelling how a building will perform is really difficult, especially for the domestic market. We often find that pressures to improve some elements of a buildings performance can have a detrimental effect on others. For example the pressure to decrease the need for energy for heating has led us to insulate our walls, floors and ceilings and reduce draughts. However this has had a knock-on effect on moisture movement, overheating, ventilation rates and hence internal air quality.
Should we be driven by the science then?
Well I think that we need to be aware of the science, but not completely reliant on it. We need to know the interactions between all the different elements of building science: the relationships between materials, ventilation, solar gain, heat sources, conductivity, noise, acoustics etc. However, we also need to rely on our knowledge of human behaviour, our own experiences of living in houses and the experience of other trusted people. This is especially important with older houses as we will not have all the facts and figures to plug into the equations that the science uses. What is the thermal capacity of your living room wall??
The need to refurbish our existing homes for the future, though, does not go away. We know that we cannot just tackle issues on a individual basis as we will just upset other elements of the building. So, we really need to address the whole house, not just one element of it. Easier said than done in a world of specialists and doubly difficult when building regulations are not joined up or compassionate towards older houses.
Using the processes expounded by the STBA and ourselves is one of the very few ways forward as we really need to look, think and act holistically.