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EIFS at composite deck flashing

EIFS at composite deck flashing

EIFS at composite deck flashing

I have EIFS to a composite deck. The deck is supported by joists and a ledger board, over EPDM as shown in attached pic. I see no metal flashing over the wood ledger. There is water intrusion to interior of building as a result. Anyone have a code reference or technical reference for details on this required flashing? thanks.

RE: EIFS at composite deck flashing

I don’t know of any code details you can point to; and that certainly seems like kind of a crappy way to leave the raw edge of EFIS panels exposed in thin air, they’ll wick water up. The codes do usually say... “and properly flashed...” when discussing these kinds of details though. Good builders used to have some concept of good details. That seems to have been lost in the rush to write prescriptive codes so that anyone can do it, if only they can follow the cookbook and its convoluted verbiage. In my world, there should be two levels of flashing there, and a water barrier behind the EFIS and ledger.

The pocket that the ledger fits in should be flashed behind the ledger and up behind the water barrier membrane. This flashing should have full height dams at the ends of the ledger to direct any water that does get behind the ledger out of the wall, not down into it at the ends. This flashing should come out over the siding mat’l. below the ledger and terminate with a drip edge. The second flashing is over the top of the ledger, goes up behind the water barrier, and terminates in a drip edge out beyond the ledger face. It should have dams at its ends too, bent up flashing mat’l., but if nothing else, at least a deep bead of caulking to form a dam. For all the trouble with PT lumber and any metal flashing mat’ls. these days, I’ve taken to using a heavy grade of peal-n-stick membrane for these flashings. When the decking runs parallel to the ledger I actually rip some small PT wedges a little less than the width of a deck board, tack and caulk them to the top of the joists, then bring the top flashing down over them. And, now the first deck board slopes to drain too.

RE: EIFS at composite deck flashing

Agree with dhengr except that EIFS typically will not wick water upward, but if it was installed as a face barrier system, it allows water behind the exterior face (don't believe the manufacturers....face barrier systems don't work). With a "raw" edge at the bottom, it was likely installed as a face barrier system, and installed incorrectly at that. If it was intended to have a drainage plane behind the insulation, it must have a weeping termination flashing (in conventional stucco, known as a weep screed...in EIFS system it is a proprietary termination flashing, depending on the manufacturer's system).

As dhengr noted, the typical codes refer to proper flashing. If you are under the IBC check Chapter 14. If this is a single family dwelling, it will likely be under the IRC which doesn't address the issue as well as the IBC, but gives a general reference (in Chapter 1) that allows you to refer to the IBC in some instances where the IRC doesn't adequately cover the subject.

Bottom line....the intent of the flashing provisions of the building codes is to prevent water from being trapped behind any cladding or façade. If that does not occur, then it is a violation of the code and considered a design/construction defect in most cases.

RE: EIFS at composite deck flashing

...and trapped water can quickly lead to fungal deterioration... I've done many reports on that 'sort of stuff...'


RE: EIFS at composite deck flashing

CONCLUSION: The lack of flashing has allowed water to intrude into the space between the ledger and rim joist and is considered a construction defect.

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