Bellingham Home Inspections (King of the House) -- Deck Flashings

No flashing! That is something that inspectors see over and over again at decks that attach to the exterior of the home. When the inspector states that there is no flashing and one is needed, virtually all sellers claim it is not necessary and they never heard of such a thing. Others involved in the real estate deal will agree or disagree, usually depending on what they have to gain or negotiate. Because a flashing is so important, for sure here in the northwest, I cannot resist posting an illustrative photo that does a wonderful job of showing what happens when there is not a proper flashing.

First, the metal flashing goes like this: The shingles would be cut so they do not touch the surface of the deck. Instead a metal flashing would go up under the shingles and out over the ledger board. The decking is installed on top of that. That way, water is caught or routed away by the metal and it does not collect on the horizontal deck boards and wick up into the siding. This flashing technique is standard, if good building practices are followed. This applies to just about anything, including cement-based siding -- although many builders ignore the rule with Hardie and other cement sidings. Obviously this whole side of the home receives heavy weather exposure. But look at the way the moisture is wicking right up into the shingles because they are touching the deck and there is, of course, no flashing. This condition can lead to serious damage of the exterior wall of the home. The probe is in an area that is soft, make that rotten.

Thanks for looking.

Steven L. Smith

Bellingham WA Home Inspector