Heating load calculation & layout plan DIN: Is a new calculation necessary?

At OWL, 3 m2 of wall heating ensured that the temperature in the bathroom is right. That was calculated, yet the majority of HB will tell you the small surface won’t bring anything anyway. People who have WH see that it does bring something.

Yes, that's the kind of thing Heizi talks about too. So, for example, regarding the shower, he says it doesn't change anything. He would do it anyway. However, for me, that's also more like only 1.5m².

Did you have the calculation done now? I only had 33°C flow temperature designed, but I have parquet almost everywhere.

Temperatures are 21°C in all living rooms and 24°C in the bathrooms.

With my two correction loops in the calculation and the window no longer being included, the laying spacing in large parts of the house is 15cm and partly 20cm. That is totally normal and nothing special. It only gets excessive in the bathrooms, where it is 5cm and wall heating.

He should first calculate several thousand euros. How much more pipe, how many hours is he working, what does the larger heating circuit distributor cost? The benchmark is then selfio with the material prices.

He only says the calculation will cost several thousand euros as detailed as I want. No, I will only do it once I have it in writing from him that he will then also execute according to the installation plan of my office. Otherwise, I spend the money and he still does it the way he thinks is right.

Seriously, it’s 300€. That’s peanuts in house construction! Just do it and tell the engineer to aim for 30°C. And then you’ll see what comes out of it. Maybe you can smooth things over with the heating installer when he sees the installation plan – it’s not rocket science. It might also turn out that your Energieeinsparverordnung house doesn’t allow such low flow temperatures and higher temperatures have to be used anyway?

The most expensive part of the entire design is the heating load calculation. Once the formula is set, it’s just about changing variables.

Wow U-values in the HLB: Exterior wall: 0.25 instead of 0.10 Window: 1.09 instead of approx. 0.85 They didn’t even look at what is actually being built... Maybe I have a much lower heating load than the first calculation showed. @OWL: Yes, also an approach. But now I already asked. Edit: I dug through your thread again. Despite the bay window and basement, you only have 5.9 kW. According to the first calculation, I have 6.1 without basement, with a simple rectangle. Even if you have a higher standard, there should actually still be something in mine. Maybe the heat pump is even oversized. Although I probably can’t change that anymore. It is already registered with the BAFA...