CE marking and the declaration of performance (DoP) are mandatory for all construction products covered by a harmonised product standard or by a European Technical Assessment.
Information on the CE marking
What kind of information needs to be mentionned in the CE marking is described in Article 9.2 CPR. The CE marking is applied on the construction product. If the manufacturer is unable to place all the information required for the CE marking on the construction product or packaging itself, the CE marking must be applied to an accompanying document (Article 9 of the Construction Products Regulation). In this case, it can be combined with the DoP (declaration of performance).
The CE marking shall always refer to the reference nubmber of the Declaration of Performance.
Language requirement CE marking
There are no language requirements for the CE marking. This is because the CE marking is applied by manufacturers on the construction products, which can be sold across borders in all EU/EEA states. This explains also why you have two sets of documentation requirement: the CE marking and the Declaration of Performance with contains pretty much the same information.