ᐅ Are the grout joints in the tiled floor too soft?

Hello dear forum members,

About 2 months after moving into our newly built house, we noticed that the grout in almost the entire tiled floor area is too soft. You can scrape it out with a fingernail or, for example, with a scrub brush by scrubbing back and forth a few times.

Of course, we informed the tiler, and an appointment with the grout manufacturer will take place soon. So far, so good/bad. The mortar company told me by phone in advance that this can "most likely" be fixed using a hardener (OH 100).

Does anyone here have experience with this? Should we insist on a complete regrouting instead?

Thank you in advance
Fugophob :-)

If you use a pressure washer on joints that you can clean with a brush, will there be anything left of the joint afterwards?

Exactly, using a pressure washer leaves nothing behind.
We’re talking about the floor INSIDE the house.

The appointment has taken place, and as expected, they want to use a hardener.
However, the risk of incorrect application is too high for me (discoloration in the natural stone, etc.).
After consulting with a lawyer, you unfortunately have to accept the type of repair offered (unless it is doomed to fail from the start, which is not the case here).

So it’s either take the risk or pay for re-grouting yourself.
Great...