Hello,
Our building contractor sells us the house as KfW70.
The planned wall construction is 40cm (24cm concrete block + 16cm external thermal insulation composite system with insulation value 032) (0.18 W/m²K).
Roof insulation is 20cm (upper floor ceiling or flat roof) (0.18 W/m²K).
13cm insulation between the base slab and screed (0.25 W/m²K).
Windows have a Uf-value of 0.93.
Air-to-water heat pump.
Central controlled ventilation system with heat recovery.
Since I am considering possibly upgrading to better windows (80-profile instead of 70-profile) and increasing the roof insulation (from 0.18 to 0.11) as well as the insulation under the base slab (from 0.25 to 0.18), I am very interested in knowing our current status.
Is it just barely 70 or perhaps already 60? How much more would be needed to reach 55?
Would a small photovoltaic system or solar water heating be necessary?
Are there any online tools available to calculate this myself? Or (free) software?
I have all the U-values etc. I have also done a heat demand calculation using a U-value calculator.
It is easy to calculate what KfW 55 pure subsidies bring: €2500 repayment bonus plus €1125 (0.25% interest rate advantage for 10 years, with bullet loan) = €3625.
Our building contractor sells us the house as KfW70.
The planned wall construction is 40cm (24cm concrete block + 16cm external thermal insulation composite system with insulation value 032) (0.18 W/m²K).
Roof insulation is 20cm (upper floor ceiling or flat roof) (0.18 W/m²K).
13cm insulation between the base slab and screed (0.25 W/m²K).
Windows have a Uf-value of 0.93.
Air-to-water heat pump.
Central controlled ventilation system with heat recovery.
Since I am considering possibly upgrading to better windows (80-profile instead of 70-profile) and increasing the roof insulation (from 0.18 to 0.11) as well as the insulation under the base slab (from 0.25 to 0.18), I am very interested in knowing our current status.
Is it just barely 70 or perhaps already 60? How much more would be needed to reach 55?
Would a small photovoltaic system or solar water heating be necessary?
Are there any online tools available to calculate this myself? Or (free) software?
I have all the U-values etc. I have also done a heat demand calculation using a U-value calculator.
It is easy to calculate what KfW 55 pure subsidies bring: €2500 repayment bonus plus €1125 (0.25% interest rate advantage for 10 years, with bullet loan) = €3625.
Our calculation was done using the Brick Energy Saving Regulation software. There is a student version available for free download, but I’m not sure if its functions are the same as the paid version. However, it offers a lot of adjustable settings. You can take a look for yourself, although the calculation is not completed with just a few clicks—it is somewhat more complex.
S
Sebastian792 Sep 2015 20:05And you have glossed over the more expensive verifications and the more intensive construction supervision – it’s not just a matter of adding a bit more insulation.
Especially since you now have a standard value for thermal bridges, whereas with KfW 55 they are calculated explicitly...
The repayment grant is definitely lost because of that...
Especially since you now have a standard value for thermal bridges, whereas with KfW 55 they are calculated explicitly...
The repayment grant is definitely lost because of that...
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