Originally Posted by
Scott Patterson
Under the step flashing you should have a "pan" that runs the length so any water the seeps behind the flashing should flow into or onto that pan.
Or other step flashing (which would be visible between the shingle courses, but is not in your photo).
The 'L' flashing is used in South Florida and other high wind areas, while step flashings are used in most of the rest of the country. At least, I've been told most of the country uses step flashings.
Having been in construction and inspection South Florida for 20 years (before I moved up here last year), all I ever saw were the 'L' flashings, but I know that step flashings are used in some areas - because you guys chastised me for our use of 'L' flashings down there
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Step flashings are subject to being lifted by the high winds (hurricanes) and having high wind driven rain blown in behind them through the gaps, whereas a continuous 'L' flashing does not suffer from those conditions.