Roof to Wall Flashing Question

[jrdepew]

All,

Three years ago I built a lanai (screened in porch but with removable windows) addition, and we have been enjoying it. Last week I was mowing and noticed some staining on the corner of the roof. Today I started investigating and found some pretty bad water damage. The corner of the roof sheathing is nearly disintegrated, as is the end of the truss and some blocking for the soffit. Looking up at the roof sheathing from under the soffit, I can see that the staining starts at the area where the corner of the house meets the roof. I must have made a flashing error there, and it must be pretty bad, because this area is very wet. I am hoping this will be obvious when I open it up the rest of the way. I cannot find a flashing detail for this intersection specifically. When I search for wall the roof intersection flashing, most of what I get is where the roof ends while still on the wall, showing the kickout flashing, etc. Does anyone have an image/link of flashing detail for this area?

I used step flashing along the roof and wrapped the last piece around the corner. All step flashing was lapped under the house wrap and a wide piece of ice and water was used to tape it up. Should I have added a 2x4 to the face of the truss tail shown below (bringing the roof of the porch around the corner of the house), and essentially flashed this like a dormer?

Unfortunately, I think the wall sheathing under the J channel shown below may be soft too. I won't know until I continue to open it up this weekend. Fingers crossed that it isn't too bad. The white trim bridges the corner of the house and the first porch post and is PVC. After replacing any damage and splicing in a new piece of house wrap, I am thinking of running a piece of metal flashing from above the roof/wall intersection where the damage is, all the way down to the bottom of the sheathing. This will be lapped under the house wrap at the top edge.

Eating some humble-pie today, as this is a big fail and I am embarrassed that I messed this up. Keeping my fingers crossed that the damage isn't too bad and I can get it all squared away over the long weekend.

Thanks for any suggestions.

-Joe

 

[dstig1]

It's a common problem. The solution is to add a kickout flashing to the roof where the wall stops above the eave. While your wall stops short (unlike the diagram below), water still can hug the wall and get behind the siding below. The wall sheathing below the eave is probably all rotted too. Pull some siding and check. Vinyl is easy to unzip if you have the special tool for it (cheap and any HD or Lowes will have them). If you have the same geometry elsewhere on the house, you should check those too and perhaps pre-emptively add the kickout. There are premade kickouts available or you can roll your own.

Edit: If the eaves extended out onto the main wall a foot or so, you probably would not see this. But yours ends right at the corner.

 

[jaxs]

I feel your pain but if it's any comfort we've all done that or worse a time or two,,,,or three. I don't think the the leak is at the corner but higher up where roof butt's the wall. It only takes one miss-applied step shingle (step flashing) to get a huge water intrusion. To be clear,did you use 6x6 L shape metal shingles or the long metal flashing with similar appearance to drip edge flipped upside down. There is no place for exposed roofing cement anywhere along the wall to roof junction.

 

[jrdepew]

I feel your pain but if it's any comfort we've all done that or worse a time or two,,,,or three. I don't think the the leak is at the corner but higher up where roof butt's the wall. It only takes one miss-applied step shingle (step flashing) to get a huge water intrusion. To be clear,did you use 6x6 L shape metal shingles or the long metal flashing with similar appearance to drip edge flipped upside down. There is no place for exposed roofing cement anywhere along the wall to roof junction.

Thanks for the pep-talk!

I did use the individual 6x6 L shaped metal flashing pieces...one for each course of shingles.

 

[dstig1]

I should add, that I also agree with Jaxs that you should check farther up the wall too. See if there is a flashing issue up there, and if so, fix it. But I would still check the wall below and add the kickout in any case.

 

[/pine]

FWIW...This is a great place to use "ZIP TAPE"...use on all flashing and drip edge seams etc...

 

[jaxs]

Someone mentioned "unzipping siding",if that's possible a foot or so up the wall maybe that will tell you if the leak is from farther up. Inspecting inside of wall from attic might tell you something. To appreciate how much water can flow through a small hole, look at how bad the leak is when a staple or nail is driven into exposed shingle surface (esp if nail is pulled or rusted out)

 

[Hay Dude]

What is the gutter/downspout set up like on the porch and house? I don’t see a gutter across the porch and wonder if there’s one on the house above?
Can you show a picture from further away so I can see the roofs & gutters?

I had a similar situation happen with a customer and it ended up being a leak on the main house after we spent many thousands tearing apart my work, which was good. The leak originated elsewhere, but showed up on my addition I built for him.

 

[2manyrocks]

Hay Dude asked a really important question. If the water from the main roof is running off onto the corner of the screened in porch, that could be causing this damage.

Malco 6-1/4 in. Siding Removal Tool 1 pc - Ace Hardware

SideSwiper model SRT2 combines the comfort and added leverage of an easy-to-grasp straight handle with the smooth unlocking motion of a burr free hook. The blade of the SRT2 is angled from the bottom plane of the handle and allows the user to keep the wrist straight while keeping knuckles well...

www.acehardware.com

 

[jrdepew]

I currently have no gutters/downspouts where the water runs off into mulch. I did add gutters to the front of the house and the other side of the porch as the runoff was hitting concrete and soaking the siding. We have tons of trees around the house, including live oaks, which have thousands of stringy seeds they release. The gutters I do have are a bear to keep clean, need to stay on top of it weekly or it can become an issue. I have been researching if any of the gutter guards are good enough at their job that I wouldn't have to clean the gutters...then maybe I could add gutters to the second story.