Every time I bring up deck flashing on an inspection I get called out!
I have had homeowners tell me that only roofs need flashing. One said he has seen window flashing but had never heard of deck flashing. Another called me a "$&*%%#@!" and that "you inspectors are just looking for stuff to mention on your reports whether they are true or not!"
Deck flashing is crucial to a deck installation. Without it water can seep into the house via the lag or through bolts. They are called "through bolts" because they go through the house to the interior.
Deck flashing, sometimes called "Z" flashing, fits under the siding and OVER the ledger beam, which is the beam attached to the house. It forces the water to the outside, where it has little chance of entering the house. It is made of metal.
Tonight I got an interesting email and phone call. On a recent inspection I mentioned that the deck flashing was missing. I further mentioned that the product I saw on the house was improperly placed and of an indeterminate material.
It seems the seller and listing agent know better. They told my client and client's agent that the deck was "built to code" and that "the flashing is indeed there, simply cut off at the top to make it look better."
Yes, that's the quote in the email...
Here are photos of the "flashing" in question. YOU be the judge!
That is the left and right view of the same ledger beam. It includes a very pretty hole extending into the interior. I would LOVE to see the wording of that code!
Ignorance is bliss I guess, but while there is no interior damage yet (the deck is only a year old) there likely will be and my client will inherit it. My job is the purchaser and his protection. My report doesn't speak to the code, onto to proper installation. And what sellers and listing agents say really has no bearing on my report.
But, who am I to question that job above?!
My recommendation: Don't buck the home inspector! And when people want to make fools of themselves, get out of the way. Just be sure to stand your ground...

So many homes do not have it, and it is very important that they do! It must be corrected.
Jay,
Construction, design, and engineering are not things for which I give clients my opinion. So far, I have avoided challenging, or contradicting an inspector's assessment. If there is an issue, I take it to another inspector or building trade professional to get another opinion. Inspectors are licensed professionals and pass tests that I could not successfully pass without a whole bunch of training and experience. I try to do my job, and let them to theirs.
I thought flashing, even if not required, was a good idea most times when you have exterior joints where moisture can collect.
Yep, a deck without flashing is a waste of money. Future headaches and repairs galore.
Jay - It's always nice when we can meet the real "experts."
Jay, it is so common to be missing out here that one has to consider it "normal" while still "wrong." (Love seeing the yellow pine by the way:)
Ellen - it is not too often that I actually see it, but deck flashing is easy to spot.
Wayne - I agree whole heartedly. We all have our niche. Sometimes they mesh with others, sometimes not!
Gary - it would bolt into the frieze board, which is the structure between the floors. As such, the deck becomes a part of the structure of the house.
Dave - I agree. I sometimes see the old caulk the edges deck installation, instead of flashing. Not good either!
John - thanks, but not sure about the "expert" thing!
Charlie - that's the commonly-used pressure-treated product here. The nicer decks use Southern Pine, pressure treated, which is much less knotty. And better looking, in my opinion. What do they use out there?
With all our hemlock and doug fir I am pretty sure there are restrictions against bringing yellow pine into the state----yellow pine is far supperior as pressure treated lumber than anything from here in my opinion because it will accept treatment all the way through.
They don't allow it into the state? Wow... I like the yellow pine, and Southern pine for that matter, because, as you say, it gets well treated. It does split though, in the process.
Hey Jay,
Very good post. I guess we have to get use to people second guessing inspectors and what we find.
Eric - no doubt. It's just that some people think they know what they don't know. Once a seller called me to say that he doesn't understand why I would bring up deck flashing since we all know there isn't any such thing. What do you do???
Jay,
Before I got into real estate I spent 20+ years as a contractor. I cringe when I see things like this. It's not rocket science to understand that water will eventually get in to any unprotected area. Just because someone sees a pressure treated board bolted to the house doesn't mean all is OK. It's the rotten band board they can't see that will eventually turn into a major structural issue.
You know that Larry and I know that. But the agent and seller know different. What can I say?
Jay,
Around here, if they have cement based siding they leave it out almost every time. Frustrating.
Hi Steve - the type of siding is quite irrelevant to whether water gets into the interior via bolts...
They cut the flashing off at the top? I don't get it.
Reuben - don't try. You won't get it. I think that stuff is roof rubber for sealing the edges of roofs and the valleys against water. If it extends the entirety of the ledger beam, it is ridiculous because it performs no function. Nonetheless, crap work is just that.
That one would be an easy fix too. Pull up the last decking boad and there you are. Good photos Jay. BTW good looking boy too. Well, unless that's you.
Jack - it is fixable, but not by the seller! They have bugged out. Yes, that's me... in my sumo wrestler uniform.
Had a deck today no flashing and the porch too. The deck also had no ledger bolts, no hangers, no structural beam, no fasteners on the three notched piers that were sunk into the ground and a few other things wrong. Decks; everyone thinks they can build one. NOT!!!
James - here's a flash - that's not a deck...