As a deck waterproofing contractor and consultant, I often see problem decks that have French doors leading out to them (see “Focus on French Doors,” 8/09). Most of the time the customer’s complaint involves a leak at the door, which usually gets blamed on the deck contractor. We often find that a sheet-metal door pan wasn’t installed — or if it was, that the door installer damaged the pan’s integrity by crushing its back lip or penetrating it with screws without caulking the penetrations. Sometimes the pan flashing is improperly placed over the building paper — as in the example shown here — rather than the other way around.
Regardless of whose fault this is, the various trades involved need to communicate more so that they work in sequence to ensure a leak-free installation. Pans and any flashings for the deck go in first, then the door can be installed.
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