Steel Buildings in Europe

Part 7: Model Construction Specification 7 - 19 6 EXECUTION SPECIFICATION 6.1 General The necessary information and technical requirements for execution of each part of the works shall be agreed and complete before commencement of execution of that part of the works. Execution of works shall comply with the requirements of EN 1090-2. 6.2 Execution classes Execution Classes (EXC1 to EXC4) may apply to the whole structure or to a part of the structure or to specific details. A structure can include several Execution Classes. A detail or group of details will normally be ascribed one Execution Class. However, the choice of an Execution Class does not necessarily have to be the same for all requirements. If no Execution Class is specified EXC2 shall apply. The list of requirements related to Execution Classes is given in Annex A.3 of EN 1090-2. Guidance for the choice of Execution Classes is given in Annex B of EN 1090-2. The choice of Execution Classes is related to Production Categories and Service Categories, with links to Consequence Classes as defined in Annex B of EN 1990. 6.3 Preparation grades Preparation grades (P1 to P3 according to ISO 8501-3) are related to the expected life of the corrosion protection and corrosivity category as defined in § 10 of EN 1090-2. Preparation grades may apply to the whole structure or to a part of the structure or to specific details. A structure can include several preparation grades. A detail or group of details will normally be ascribed one preparation grade. 6.4 Geometrical tolerances Two types of geometrical tolerances are defined in § 11 of EN 1090-2: a) Essential tolerances shall be in accordance with Annex D.1 of EN 1090-2. The values specified are permitted deviations. - Manufacturing tolerances are described in § 11.2.2 of EN 1090-2 - Erection tolerances are described in § 11.2.3 of EN 1090-2.