Consumers buying construction products − whether they carry a CE marking or not − must make sure the product is suitable for their intended use. The seller must be able to advise you about product suitability for different purposes.
The CE marking can be affixed to the construction product itself or its packaging. A CE marking for a construction product is usually based on a product-specific harmonised product standard. The product-specific standard specifies which technical data must be provided about the product in conjunction with the CE marking. The content of the marking varies a lot between different product groups. There are products with labelling containing a lot of technical data, while others may carry a highly simplified labelling.
The CE marking is compulsory for products that fall within the scope of an harmonised standard; as to other construction products the marking is voluntary. Therefore you may find various products intended for the same purpose for sale at a retail store, with some carrying a CE marking and others not.