My company specializes in installing waterproof decks, but I often also get calls to fix existing decks that are leaking or coming apart. Many times, these jobs are familiar. They are ones we had bid on to build originally, but didn't get—probably because we had priced the jobs to use the best materials available and install them correctly.
The worst dry-rot damage we see usually occurs where drains and scuppers penetrate a deck. We do see some problems with drip edges on open decks, but not as many, as edge flashings aren't subjected to as much water as drains and scuppers are.
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