Site wind and snow load check

A site wind and snow load check is a preventive step at design and installation. It confirms that the mounting structure, clamps and modules can carry the wind, snow and other loads expected at the site. It is recommended for Bad Module Clamping and Defective Mounting Structure. Do it together with using only compatible clamps and mounting structures and following the manufacturer's mounting instructions. Mounting structures often fail because they were not designed for the site's typical wind or snow loads, did not meet the static calculations, or had weak anchorage to the ground or roof. Another cause is that nobody checked whether the roof could carry the added load. A module's load rating holds only for the approved mounting methods. The professional installer is responsible for calculating the mechanical loads for the actual system design. Snow loads on a roof are worked out from ground snow load maps, such as those in Eurocode 1, using shape, thermal and exposure factors. Snow drift often drives the load. Module certification tests apply an even load for a short time. Real snow can sit for weeks or months, spread unevenly and pile up at the lower edge, so a module rating alone may not be enough. Snowdrift can pile up large amounts of dense snow in specific spots. In one reported case, drifting snow destroyed modules that had been clamped at the corners against the manufacturer's recommendations. The check does not repair existing damage. Mounting structures that pose a direct safety risk should be repaired or replaced, and regular system inspections are still advised.

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• sentence 1: support check: partial - Passages say to check local wind/snow load and use compatible parts as a preventive (recommended) action, but do not explicitly place it at design/installation or say it confirms capacity of structure, clamps and modules.
• sentence 2: support check: partial - The recommended preventive action pairs checking local loads with compatible clamps/structures and following manufacturer instructions for both failure types, but 'recommended' and 'do it together' are only implied by the table's structure.
• sentence 5: support check: partial - Passage says roof load derives from ground snow load using shape, thermal and exposure coefficients with Eurocode 1 maps and that drift often causes snow load, but 'often drives the load' is a mild paraphrase and maps are 'such as' fine; minor overreach is none, yet drift claim is about shape/snow drift generally.
• sentence 8: support check: partial - Passages state that unsafe structures should be replaced or repaired and regular inspections are advised, but nothing explicitly says the load check does not repair existing damage (only implied by it being preventive). -->