ᐅ Defect in “barefoot grid” – Expert assessment requested Barefoot grid

I am currently involved in a dispute with a supplier of so-called "barefoot grids" (grating for barefoot-accessible areas, such as terrace exits) and would appreciate a professional assessment based on practical experience.

The order confirmation specifies a profile spacing of 8–10 mm (0.3–0.4 inches). From what I have seen in the industry, a spacing of about 9–10 mm (0.4 inches) between the slats is standard.

However, for the delivered grids, the gap at the edge measures about 20 mm (0.8 inches), while the central gaps fall within the specified range. Additionally, the gratings show manufacturing defects such as warping along their entire length due to galvanizing and, in some areas, burrs or lips. When straightened during installation, these cause differences in length. The total length is 12 meters (39.4 feet), made up of 8 sections, and each shows warping of 2–4 mm (0.08–0.16 inches) in the middle, which significantly affects the overall length since the gratings cannot be laid flat.

Before ordering, sample images were provided, showing slats designed quite differently (extending almost to the edge with much smaller edge gaps).

My questions to the knowledgeable members here:

Would you consider this design flawed for a product described as a "barefoot grid," or would you still classify it as normal?

Are edge gaps of this size common in this type of grating from a technical point of view?

Do you see a relevant risk of injury (e.g., to toes) from these dimensions?

In your experience, would an expert or inspector be able to assess from these features whether the product is suitable for barefoot walking?

Background: The matter is now in legal proceedings, and I am considering whether an expert report would likely favor or disadvantage the client based on these characteristics. The landscaping contractor has already confirmed in writing that the grids are unsuitable for barefoot use and does not accept liability for installation. However, this is only his opinion. What concerns me more is how an expert would judge this.

I welcome factual assessments from professionals in planning, landscaping, metalwork, or expert practice.

Attached are also three sample images sent by the manufacturer in advance.
#please_only_professional_feedback

The parts are custom-made, right?

It seems the colleague was trying to save on filler rods each time.

I can’t tell you how a court-appointed expert would judge this, but I remember that our family once needed a corner piece for a similar structure, which was then made by a metalworker. At the time, the outer distances also seemed quite large to me, which meant we could barely find a metalworker willing to produce the part with an identical division.

In the end, the metalworker made a part with “his” division, which resulted in a “half division” at the corner pieces – the filler rods were each offset by half. That’s how the metalworker built it.

Unfortunately, I don’t have any pictures – the terrace has since been remodeled...