This part of ENV 1090 is aplicable except as follows: (106) This part of ENV 1090 specifies particular requirements for the execution of steel structures produced from cold formed thin gauge components and sheeting designated construction classes I and II in ENV 1993-1-2. Note 1: Supplementary rules for execution of structures with cold formed closed hollow sections are given in ENV 1090-4. Note 2: The construction classes differentiate between levels of reliability. Note 3: Requirements for execution of sheeting in construction class III may be specified in national rules. Note 4: This European Prestandard does not cover requirements for water tightness and draught resistance of sheeting.