Roof to wall flashing

[Chuck Swan]

New construction on a home in Utah. Stucco with some wood trim. Horizontal intersection with the wall has L flashing installed. I have generally seen the flashing under the siding and on top of the 1st row of shingles. To improve appearance, the contractor nailed another row of shingles on top of the flashing and then put a trim piece on the wall without any caulk or flashing on the horizontal trim. No clearance between trim and roof. Recommendations?

[Lon Henderson]

I see this done quite often and I don't see any issue with shingles on the foot of the flashing. Even though nails are through the flashing, I never see leaks from this. The trim piece should be caulked (or flashed along the top to the siding above) just to prevent water from being trapped behind the trim. Of course, we just can't see if the flashing is properly installed underneath. Assuming that the trim is just for aesthetics it still would have been better, though maybe not necessary to have a 2" gap at the bottom.

However, the stucco head wall, is a different matter. The bottom edge should be at least 2" above the shingled deck. Also, the bottom edge should have a weep screed. I can't tell in your photo how the bottom edge was flashed.

In most of Utah as in Colorado where I am, builders get away with lazy stucco applications because of our low humidity and low precipitation. But.......snow build up against the head wall on the roof could cause problems with this application, in my opinion.

Since it is new construction, apparently, the code enforcement officer doesn't share my concerns, and therefore, neither will the builder. For things like this, I just tell the buyers what I think and to do a careful re-inspection of these areas at their one year anniversary of the warranty that most builders have. I also suggest that they express in writing, my concerns, to the builder, just in case somewhere down the road a problem does develop. Sometimes, that paper trail can help out with a reluctant builder after the warranty expired.

[Jerry Peck]

To improve appearance, the contractor nailed another row of shingles on top of the flashing

The contractor just ruined that top base/wall flashing.

Pull the shingles up, replace the flashing (which can either be under the shingles and the shingles sealed to the flashing with plastic roof cement, or, place the flashing over the shingles and seal the flashing down to the shingles with plastic roof cement to keep wind driven rain out). and, if desired for a more finished appearance one can glue shingles to the flashing with plastic roof cement ... just do not nail through it as nailing through a flashing perforates the flashing and makes the flashing so it can leak.

All the walls should have at least 2" below the wall covering (stucco,siding,etc) to the roof covering (the shingles).

[Chuck Swan]

Thank you for your help. I have already noted the min 2" clearance. I could see having the wood siding trimmed up, but what about the stucco - wouldn't it be a major rework to correct the stucco and the weep screed?

[Jerry Peck]

but what about the stucco - wouldn't it be a major rework to correct the stucco and the weep screed?

Yes, which is why that will likely not be done, but it is still wrong and still needs to be written up.

Only by writing things up do those things come to the attention of enough people that those things may - may - eventually start being done correctly on the new houses.

[Kristi Silber]

I agree with some of the points made, for instance that it's wrong there's no gap...but whether its a problem in reality is different. How far does the roof overhang this area, and how far above it is it?

I was surprised to hear that usually you saw flashing on top of the shingles. This is where you'd use step flashing, which is effective and concealed.

There should be flashing at the top. They might have put shingles over it. Those nails are okay, although they should have caulked them. Sometimes nails show, that's normal and in accordance with installation instructions.

Before paying a bundle of money to fix this, I think it's important to consider how likely it is to be a problem. Need more detail about the flashing on the side. And it's not really stucco, is it? EIFS or maybe stucco panels?

EDIT: Ach, shouldn't be writing this late. Take the above with a grain of salt, don't hold me to it. Missed two of the three photos!

[Lon Henderson]

The step flashing is used along the rake walls, but on the head wall it is long lengths of flashing with the foot of the flashing sitting on top of the top course of shingles. In the photos, they laid a cosmetic course of shingle tabs on top of the flashing. I agree with Jerry that it should never be nailed down, but I see it nailed down all the time. I never see resulting leaks although the potential for a leak is real. I am surprised that code enforcement let that builder get away with it, but those guys miss things and that it why we get paid to inspect new construction. :D

As for the stucco, that is probably not EIFS but probably what we call hard coat here and in Utah. Most commonly the 3 coat method. And around these parts, it is rarely installed properly, but rarely gives trouble because of our dry climate. Back east and down south, installers could never get away with the kind of installations that we regularly see here.

[Kristi Silber]

Hardcoat is very common here; about a quarter to a third of the houses I survey are stucco. But the difference is that they are mostly pre-1940 and in a different region, so who was I to question whether it is in fact "real" stucco? I never see such a straight, well-defined edge, but that could be due to different methods. I thought it seemed kind of thin for hardcoat, but it's hard to tell.

Where in Utah is the home?



The step flashing is used along the rake walls, but on the head wall it is long lengths of flashing with the foot of the flashing sitting on top of the top course of shingles. In the photos, they laid a cosmetic course of shingle tabs on top of the flashing.Yes, I know, that's what I was getting at before. I agree with Jerry that it should never be nailed down, but I see it nailed down all the time. I never see resulting leaks although the potential for a leak is real. I am surprised that code enforcement let that builder get away with it, but those guys miss things and that it why we get paid to inspect new construction.

I couldn't find anything in the ICC about not nailing flashing. Step flashing shouldn't be attached to the wall, but that's different. I have a book on home building that says to nail it to the roof (but it's not a new book). As you said, it's done all the time. If it's not been a problem so far, why believe that it will be? Sure, there's potential for leaks, but how big is that potential, considering the climate, overhang, pitch, etc.?

On the other hand, the work as a whole doesn't really strike confidence in the contractor. What's up with the "shingles" going behind that long trim board?

[Jerry McCarthy]

Totally wrong as voiced by others. Then there's the exposed nails...... arghhhhh! :(

[Mark Parlee]

First picture shows a trim board that appears to be applied over the face of the siding.
This will allow moisture to migrate between the two materials and promote degradation. this joint has no protection to keep the moisture out and sealant is temporary.
Code says all protruding wood trims are to be protected with a metal flashing.

[Jerry Peck]

Code says all protruding wood trims are to be protected with a metal flashing.

And what does it say about protruding cement board such as HardieBoard trim?

[Mark Parlee]

Jerry
I have thought about this very thing. Fortunatly Hardie address this specifically in their installation instructions and calls for a metal flashing over any of their protruding trims.

If we could show that the product contained wood fibers would that not constitute wood trim?

[Jerry Peck]

I have thought about this very thing. Fortunatly Hardie address this specifically in their installation instructions and calls for a metal flashing over any of their protruding trims.

The point was that the code specifically, and only, addresses "wood" trim ... other than that other products should be installed in accordance to their installation instructions as you mentioned.


If we could show that the product contained wood fibers would that not constitute wood trim?

Not really, because those other composition products are not "wood", they are "composition", and again, though, they would need to be installed in accordance with their instructions.

[Mark Parlee]

Jerry

Some of the problems I see are the lack of good instructions when it comes to the finer details of installation of some of these products.
Code does call for a metal flashing to protect protruding wood trims. This is good to protect the wood against moisture intruding into the wood product but it also allows incidental moisture a place to egress out of the siding assembly. This is contingent of course on the installer not sealing the siding to the metal and leaving the siding clear by 1/4" minimum, 3/8" is better.
Hardie does have explicit instructions to leave the siding clear of the metal by 1/4" and not caulk.
Some of the other trims such as the PVC would not have the code requirement of the metal flashing protection due to the fact they are not wood. Even so it is still a good idea to have the metal L chanel over them because it protects against moisture intrusion at this joint. Relying on sealant at this particular joint is not a good idea due to it needing to be maintained and you know how well most of us do maintenance on our homes.

[Jerry Peck]

JCode does call for a metal flashing to protect protruding wood trims. This is good to protect the wood against moisture intruding into the wood product but it also allows incidental moisture a place to egress out of the siding assembly.

I'm not saying that it is not 'needed' or not a 'good practice', only that the code is specific in its requirement to "wood".

With EIFS, the top of the projecting trims is required to be slope, 1:2 as I recall (1" fall to 2" run), but how many do you see that way?

[Mark Parlee]

I'm not saying that it is not 'needed' or not a 'good practice', only that the code is specific in its requirement to "wood".

With EIFS, the top of the projecting trims is required to be slope, 1:2 as I recall (1" fall to 2" run), but how many do you see that way?

Jerry

I understood what you were saying, just trying to clarify further. I know we are on the same side of things here, sometimes hard to communicate in written word only.

EIFS 1:2 you are correct. It is not very often you see it that way. I do prefer the more crisp look of it being square but it has proved to be a problem so we are stuck with the 1:2.

[Kristi Silber]

Notice: Owens Corning recommends the use of nails as the
preferred method of attaching shingles to wood decking or
other nailable surface.



I've been reading and thinking about the issue of the nailing. In MN, unless you get the Building and Inspection Division to OK use of another fasterner, shingles need to be nailed. Shingle manufacturers also recommend nailing. Adhesive is an aid, not a substitute. Flashing is nailed to roof and not the wall, allowing movement between the two. Nailing to the roof instead of the wall allows you to also embed the flashing (and/or shingles) in adhesive.

They should have caulked them, though.