KfW 55 Single-family house - Brick or Ytong?

Hello everyone,

we are currently still comparing the different construction companies:

- 1 construction company builds exclusively with Liapor
- 1 construction company builds exclusively with brick
- 1 construction company builds with Ytong - surcharge for brick is €5,000.

We are building a KFW55 single-family house with an air-water heat pump and central ventilation system.

I know the advantages and disadvantages of the respective building materials, but I wanted to hear your opinion here once again, possibly also in connection with the ventilation system.

The company that builds with Liapor is by far the most expensive, also due to the building material. However, I actually see no added value here at all, or no added value that justifies the sometimes surcharges of up to €10k.

Currently, we are actually considering building with Ytong. We favor a construction company that builds with Ytong as standard, surcharge as mentioned above is €5k.

We favor brick, but the question really arises: why? Will I notice anything afterwards at all?

My cousin has been living in his Ytong house for 4 years and has not even complained about the sound insulation...

What do you think?

The added value is likely in the wall thickness, which the air-water heat pump may compensate for given the rather poor building envelope. So if the offered masonry thicknesses are the same, i.e., the lambda values should not be so significant. But this should already be determined by the building permit.

The building physics for the brick is different, as it consists of a composite material.

Currently, the consideration is actually to build with Ytong. We favor a construction company that builds with Ytong as standard, surcharge as above is 5k.

The small surcharge suggests that quite a few of their customers choose this option. If you are one of four customers who choose this option, then enjoy it if you consider it better; if, on the other hand, you are one of twenty customers and the other 95% choose the other building material, then you wisely do so as well.

A construction company said yesterday that Ytong might not be the best choice in an earthquake zone. What do you think about that? Is there any truth to it?

And you think a structural engineer is going to answer you here???

Maybe someone is also building in an earthquake zone and is asking the same question or also has information from a construction company?