ᐅ Residual current circuit breakers with arc fault detection in prefabricated houses

Hello dear forum,

We are currently building a new house with Keitel-Haus. In the additional cost invoice for the selections, we were informed that we need to install residual current circuit breakers with arc fault detection because our house will be built after December 18, 2017. After doing some research, I found out that this is due to a new VDE standard, which requires these devices to be installed, among other places, in wood-based constructions.

According to the insurance company, these are not necessary unless explicitly required by the local authorities. For the insurance, only what is specified in the regional building code regarding fire protection counts. The switches would cost almost 3,000€ for 11 circuits, which we would prefer to avoid...

Could you please clarify how necessary these are and whether they are really mandatory?

Best regards

In Germany, arc fault detection devices have been required since February 2016 for various room uses in new buildings according to the updated DIN VDE 0100-420; a transition period was in place until December 18, 2017. This applies to final circuits with operating currents up to 16A, when supplying bedrooms or living rooms in homes, daycare centers, or accessible dwellings compliant with DIN 18040-2.

The same applies to rooms with increased fire risk (fire-hazardous workplaces), rooms containing combustible building materials, as well as rooms where irreplaceable assets are at risk. Their use is also recommended for all other final circuits with operating currents less than or equal to 16A. However, the use of arc fault detection devices in Germany is not legally mandatory and is therefore voluntary, because DIN VDE 0100-420 has not yet been incorporated into the state building regulations as a technical building requirement.

Therefore, you do not need them. The price is about 100 € each.

Good to know! Thanks for the information, this concerns us as well, and our builder is asking for a lot of money that he can now safely forget about.

I am currently facing the same issue. Our electrician and the builder both say that this complies with the state of the art according to DIN standards and that the components have to be installed. Otherwise, they would reject any warranty claims, which I can understand.

We have now agreed to group individual rooms onto one circuit where it makes sense, in order to reduce the number of switches. By the way, for us, the cost including installation is almost €300 each.

You can have your own opinion about this, but when it comes to safety, it’s not something you should cut corners on.

You are being seriously misled.

Which warranty are you actually refusing? For what exactly? A warranty that your house will burn down? They wouldn’t cover that anyway... That’s the responsibility of the insurance company. And what kind of safety do you mean? Either the electrician has done a poor job, which can be dangerous, or they install everything according to the established standards that have been in place for decades, and everything is fine. In my view, this is currently a huge money-making scheme driven by fear. Just the fact that everyone claims it’s mandatory, even though it is not listed in any building code or regulation. My insurance company also says that only the state building regulations count; if my house burns down due to an arc fault, they will still pay out.