We are planning to build a dormer on our townhouse and have found a construction drawing that fits perfectly with our idea. The problem is that the U-value for the roof and wall is too high. I have tried using the programs linked here on byggahus, but I can't make sense of them. I just can't figure it out. Is there anyone who has the time and inclination to look at the construction drawing and give tips on what we can adjust to meet the U-value requirements? 
What is the threshold in Sweden?
(If we now take 'point' values Here in Switzerland, it is 170 mW/m² °K (but as a Swede, one would want to use C, which is the same scale) for new constructions, 270 mW/m² °K for renovations, and 200 mW/m² °K to get a subsidy.
If I get the values, I can calculate it. Meanwhile, I'll check these constructions... back shortly...
(If we now take 'point' values
Here in Switzerland, it is 170 mW/m² °K (but as a Swede, one would want to use C, which is the same scale) for new constructions, 270 mW/m² °K for renovations, and 200 mW/m² °K to get a subsidy.If I get the values, I can calculate it. Meanwhile, I'll check these constructions... back shortly...
Here.
In the example, I used Rockwool mineral wool, with a lambda of 36 mW/m °K, which is a common average, and I believe you can find Rockwool in Sweden. Wood wool is nicer but the prices have probably skyrocketed in Sweden as well?
So you have U-values of 180 mW/m² °K in the roof and 170 mW/m² °K in the wall. Isn't that really enough?
Yes, and as a weather station, I used Basel, I can't be bothered to dig up a Swedish station, especially not for a free job, but the annual average here is only about 1 °C warmer (than my hometown, before the expulsion, Stockholm).
In the example, I used Rockwool mineral wool, with a lambda of 36 mW/m °K, which is a common average, and I believe you can find Rockwool in Sweden. Wood wool is nicer but the prices have probably skyrocketed in Sweden as well?
So you have U-values of 180 mW/m² °K in the roof and 170 mW/m² °K in the wall. Isn't that really enough?
Yes, and as a weather station, I used Basel, I can't be bothered to dig up a Swedish station, especially not for a free job, but the annual average here is only about 1 °C warmer (than my hometown, before the expulsion, Stockholm).
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