A guide into renovation package concepts for mass retrofit of different types of buildings with prefabricated elements for (n)ZEB performance

Zero or nearly zero energy houses ((n)ZEB) are in fact houses that meet their energy demand by on site production of (renewable) energy, that is, by limiting consumption of fossil fuels and replacing them with local, building-connected generation. There is an ongoing discussion whether energy neutral buildings could sometimes be a better option, namely, the houses that use only renewable energy, which can be produced elsewhere, either in the direct vicinity, or by the classic grid. National power supply systems are also in transition in most countries, and they will eventually shift towards renewable energy production. For the housing sector, however, it has been decided to start as locally as possible, and not to wait until the whole system has been transformed. In some countries, local district heating will still be the major option to explore. This is the starting point in analysing retrofitting concepts for housing. With this in mind, to create zero energy houses, or nearly zero energy houses 4 main areas can be targeted: 1. (Local) production of renewable energy; 2. Reduction of energy loss in buildings; 3. Adaptation of building use; 4. Changing inhabitant behaviour. This book approach focuses mainly on Steps 1 and 2, assuming the usual mode of operations for Steps 3 and 4. Although it might turn out that to reach real zero energy targets and possibly beyond energy plus houses, which, for instance, include energy generation for electric driving, Steps 3 ad 4 might have to be addressed as well. Within Step 3, for instance, there is an option that the heated (or cooled) area should be reduced square wise. Within Step 4, there is an option that average temperature levels are reduced or differentiated among different rooms. In some retrofit concepts, Steps 3 and 4 are already addressed. We will also consider them within ?Concepts? section. The approach focuses mainly on heating and ventilation (cooling), since this energy demand is related to the building itself. Household-related energy use will not be influenced by retrofitting directly. Optimization in energy and materials input will mainly be ensured by optimization of heating/ventilation. If Steps 3 and 4 are left out, household energy is a set demand that can be supplied by the related given amount of extra energy generation. This will be shortly addressed in Chapters 2 and 3C.EU Framework Programme for Research and Innovation H2020 under grant agreement No 63347