BS EN 13497:2021 pdf free download – Thermal insulation products for building applications – Determination of the resistance to impact of external thermal insulation composite systems (ETICS).
7.2 Test procedure
The test specimen shall be placed on a support according to 5.4.
The steel ball is dropped from the specified height onto the surface of the test specimen, as determined in Table 1, see Figure 2. For each energy level chosen, five separate impacts are performed at different positions of the test specimen. The minimum distance between any impact position and the specimen edges shall be at least 100 mm. The minimum distance between any impact position and the insulation board edges shall be at least 100 mm, i.e. no impact on a joint between insulation boards if more than one board is used to prepare the test specimen. The centre to centre distance between any two impacts shall be at least 100 mm.
In case of possible rebound, the steel ball shall be caught or diverted away to avoid a second impact.
If a perforated tube is used to control descent of the steel ball, it can be placed directly onto the test specimen surface. Alternatively, an unperforated tube can be used but this should be lifted above the specimen surface to allow the compressed air to be dissipated immediately before impact occurs. The verticality of the tube shall be checked before each individual test. The tube may be used for diverting the steel ball before a second impact.
Observations shall be taken at each impact zone. If one or more of the following defects are observed, no further evaluation is necessary:
— delamination between the finishing layer and the base coat;
— delamination between the base coat and the insulation product;
— delamination within the base coat;
— visibility of the reinforcement;
— perforation of the finishing layer and/or base coat.
— cracks in the impacted surface wider than 0,2 mm.
If none of these defects are observed, state it in the test report and examine the cracks on each impact zone. The impact zone shall be examined from several angles with a bright white light to measure the maximum width of the widest crack:
— cracks in the external surface of the render system. The maximum width of the widest crack is measured with the gauge specified in 5.3; record in increments of 0,05 mm or state no cracks observed
— cracks in the rear face of the render system. The maximum width of the widest crack is measured with the gauge specified in 5.3; record in increments of 0,05 mm or state no cracks observed;
NOTE Separation of the layers can be done mechanically with a suitable knife/hot wire. Alternatively, some thermal insulation products can be dissolved using solvents. If this process is used, it is advised to follow the safety procedures associated with the use and disposal of the particular solvent.
— spalling of grains at the point of impact;
— Report the maximum depth for each impact zone to the nearest mm or state no deformation observed.