With sectional doors for parquet or laminate flooring, key and slot joints for individual sections are applied. However, these sections are opened and closed frequently. To enable a robust but permanent flexible key and slot joint, specified dimensions are critical and must be adhered to. This is particularly important in the case of significant temperature differences or inaccurate dimensions, where the door could be locked or positioned incorrectly. The measurement of the key and slot joint is therefore critical in ensuring the correct manufacturing dimensions.