So we have the first reaction from Kann Bausysteme:
After evaluating the image material, it appears that, among other things, packages from two different batches or production plants were received. Only in this way can the color deviations be explained.
In principle, we manufacture the same products at various production sites in Germany. For the production of our products, we use natural raw materials such as sand, gravel, grit, cement, water, etc. These have a significant influence on the color and surface of our products. Since the raw materials used are natural products subject to regional quality fluctuations, despite our careful and elaborate quality controls, we cannot technically avoid color deviations in the finished products.
Since all concrete product manufacturers are equally affected by this, the relevant regulations for paving stones (DIN EN 1338 – concrete paving stones) also contain the following note:
"Deviations in color intensity and surface texture of the paving stones can be caused by unavoidable variations in coloring, fluctuations in the properties of the raw materials and during hardening, and are not considered significant."
Furthermore, weathering and mechanical stress over time particularly lead to changes in the color and surface structure of the concrete products. The existing color deviations therefore partially align noticeably over time.
Regarding photos and product images, we explicitly point out in all our documents that various factors such as camera positions, lighting, sunlight, shadow casting, surroundings, monitor settings, etc. can partially strongly influence the color and surface effect.
Since the product as a whole does not meet your expectations, we hereby offer you, on the basis of goodwill and without recognition of any legal obligation, a one-time discount of 50% on the entire area. We would transfer this amount to you upon presentation of an appropriate bank account and original invoice.
I also found the following text on the OBI site and on Kann’s site, which serves as a description for the paving stones:
The new trend design paving stone Parchetto brings the charm of lively architecture to your home with its two naturally appearing, light color nuances. The functionality and straightforwardness ensure a chic and modern ambiance in all areas around the house – on terraces, walkways, and even frequently used driveways. The nine different stone formats of the Parchetto paving stone create a varied surface pattern and are already combined almost ready for laying in the pallet arrangement. This also makes laying quick and easy for inexperienced DIYers. The delivery unit already includes the appropriate number of 9 individual stone formats (40 x 10 cm x 7.5 cm, 30 x 10 cm x 7.5 cm, 20 x 10 cm x 7.5 cm, 40 x 12 cm x 7.5 cm, 30 x 12 cm x 7.5 cm, 20 x 12 cm x 7.5 cm, 40 x 18 cm x 7.5 cm, 30 x 18 cm x 7.5 cm, 20 x 18 cm x 7.5 cm), which each cover an area of 0.96 m².
We are now torn. Since Kann Bausysteme very quickly offered us a 50% discount as a concession, I think something is not right there. But there is also the risk of pushing it too far if we now insist on an on-site appointment and they withdraw the offer.
What bothers me, however, is that it is advertised that an inexperienced handyman can lay the stones because they are combined almost ready for laying.
We do not yet know whether we should accept this and manually swap stones afterwards or what else we should demand. Our paver says we should definitely continue to insist on an on-site appointment.