I do not find the windows themselves impressive even with Uw:0.84. We installed plastic/aluminum with a Uw: 0.69 and only have KFW 55 but not because of the windows :-)
Hello, our architect planned our house with the following features: 48 cm aerated concrete, triple glazing, insulation between rafters, 60 mm insulation above rafters, central ventilation system, photovoltaic system, and now we only achieve KfW 55 standard. Allegedly, the building envelope would not be sufficient for KfW 40. Does anyone have experience with this? Thanks for your support.
The total volume of the house also plays a role in the calculation. As a comparison: we have 24 mm insulation between rafters + 140 mm insulation above rafters and achieve KfW40+ and Passive House standard. What is under the slab (for us 14 cm XPS). For KfW40, you need an energy consultant anyway, who will tell you where the issues lie ...
The total volume of the house also plays a role in the calculation. As a comparison: we have 24cm cavity insulation between rafters + 140mm insulation above rafters and achieve KfW40+ and Passive House standard. What is below the floor slab (for us 14cm XPS). For KfW40 you need an energy consultant anyway, who will tell you where the weak points are ...
