| Method | Tools | Best for | |--------|-------|-----------| | Visual inspection | Torch, mirror on rod | Blockages near top or bottom openings | | Water test | Garden hose | Detecting presence/location of blockage | | Rodding and probing | Flexible drain rods | Finding soft blockages and approximate depth | | CCTV inspection | Endoscopic camera | Precise location, identification of debris type, pipe condition |
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CCTV revealed a compacted mass of moss and small twigs 3m below the gutter outlet, just above a 45° bend. | Method | Tools | Best for |