When talking about zero-energy building people might forget what the initial philosophy is behind the concept.
One of the main reasons is to decrease the carbon footprint and the CO2 emissions. This is why in the UK they prefer to work with the terminology of zero carbon building.
People tend to believe that the main advantage of making the building envelope people airtight is the aspect of energy saving. But I would like to challenge this point. It is actually the full lifecycle that needs to be taken in consideration when considering energy saving. All the materials, labour and transportation needed to make the building envelope airtight contribute to a drastic increase of the overall lifecycle carbon footprint.
Considering the facts, does that mean building airtight is not a feasible choice? By no means!
Mind that the airtight aspect is just one of the many components of zero-energy building.
Additionally there is the advantage of the health aspect, efficiency of the ventilation with or without heat recovery and so on and so forth.
The point I elaborated on in this entry and I would like to gave your opinion on is lifecycle analysis.
Sustainable design often goes hand in hand with lifecycle analysis in order to map out the carbon footprint. The concept of zero-energy buildings is to reduce the carbon footprint but lifecycle analysis is rarely used to map out the actual improvement.
Could lifecycle analysis offer a solution to map out possible problem area's? A communication tool? A way to initiate in sustainable design concerning airtight building?
Or are there already studies conducted concerning lifecycle analysis with airtight building?