The energy (nonrenewable primary energy) used to manufacture a 200 square meters straw bale insulated exterior wall of a one-
Detailed comparison of wall structures throughout their life cycle
The energy demand for manufacturing as well as the transmission heat loss of three different wall structures, each featuring two different insulation qualities, will be analyzed.
Minimum standard of a passive house: U-
Upscale standard of a passive house: U-
HR MW: Mineral wool insulated timber frame wall
StB WDVS: Reinforced concrete wall with a thermal insulation system based on polystyrene
QT50 : Amount of the transmission heat loss corresponding to a 50 years’ life span of the construction element in kWh per sqm of the exterior wall and an assumed primary energy factor of the heating installation of 0,6
PEI nre: Energy demand for the manufacturing of the wall structures in kWh per sqm (nonrenewable primary energy)
At the very first day of its life span the reinforced concrete wall has used as much nonrenewable primary energy as the straw bale wall not only for its manufacturing but also for its usage over a period of 50 years (according to the transmission heat loss). In other words, as the energy consumption for its manufacturing is tremendous, an even properly insulated reinforced concrete wall leaves the same ecological footprint at its very first day of life as the straw bale wall when its life span has expired. And the disposal, which is much more ecologically friendly when it comes to walls made of straw, wood and clay, isn’t even taken into account.