ostsee
2011-11-26 13:04:27
- #1
Hello everyone,
one more topic that I didn’t quite understand during the meetings with the developer and the energy consultant.
We are planning to use windows with triple glazing and a U-value of 0.7 W/m²K.
For the determination of the primary energy demand, the energy consultant has now averaged the U-value from the frame and the glass area for the windows.
For the frame, he assumed a value of 1.1 and for the window a value of 0.7. That makes (1.1+0.7)/2 = 0.9 for him.
He then used this value of 0.9 as the U-value for our planned 46.19m² window area in his calculations.
Since we are quite close between the thresholds for Kfw 40 and KFW 55 and the house currently meets Kfw 55, we have to spend a little more money for better insulation, etc.
The question for me now is whether one can also achieve an advantage in terms of the U-value through a more detailed differentiation of the calculation, for example for the windows.
If you take, for example, a small window where the ratio between frame and glass area is almost 1:1, and a window where the ratio is clearly shifted towards the glass area, then I come to completely different relations in terms of the U-value with my layman’s view.
Another question for me is what possibilities there are to improve the U-value of the frame as well. So far, our developer has not been able to give me any information about the actual U-value of the frame.
And one last question is whether there are any tools on the internet that allow you to determine the energy demand yourself depending on certain parameters.
Many thanks for tips & tricks :)
Ostsee
one more topic that I didn’t quite understand during the meetings with the developer and the energy consultant.
We are planning to use windows with triple glazing and a U-value of 0.7 W/m²K.
For the determination of the primary energy demand, the energy consultant has now averaged the U-value from the frame and the glass area for the windows.
For the frame, he assumed a value of 1.1 and for the window a value of 0.7. That makes (1.1+0.7)/2 = 0.9 for him.
He then used this value of 0.9 as the U-value for our planned 46.19m² window area in his calculations.
Since we are quite close between the thresholds for Kfw 40 and KFW 55 and the house currently meets Kfw 55, we have to spend a little more money for better insulation, etc.
The question for me now is whether one can also achieve an advantage in terms of the U-value through a more detailed differentiation of the calculation, for example for the windows.
If you take, for example, a small window where the ratio between frame and glass area is almost 1:1, and a window where the ratio is clearly shifted towards the glass area, then I come to completely different relations in terms of the U-value with my layman’s view.
Another question for me is what possibilities there are to improve the U-value of the frame as well. So far, our developer has not been able to give me any information about the actual U-value of the frame.
And one last question is whether there are any tools on the internet that allow you to determine the energy demand yourself depending on certain parameters.
Many thanks for tips & tricks :)
Ostsee