Short story:

Purchased house with older roof and chimney cap that needed repair - no evidence of leaking around that area, planned for needed updates

Had chimney top rebuilt roof replaced within a month of moving in and made it through some heavy snow and rain this season with no problems - until yesterday...

Slow leak is occurring at bottom of slope near chimney corner - roofing company says cracks in mortar and other masonry is causing it.

To my eye flashing and bricks look pretty good.  Does anyone see any particular problems?

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That's a flashing leak. Water seeping through mortar stains but doesn't wet like that. It is odd to see that style of flashing on an asphalt roof and it seems a little short of the horizontal run under the shingles, at least around here. We would typically use lead flashing 4" minimum on all sides under the shingles.

Is that 2nd picture from the top down? It looks like the the water shingles are cut over the flashing in a way that water will drive under them.

ETA: I presume whatever water going under those top shingles is still mostly coming out on top of the head flashing. That whole detail is just weird.

If it was running down the mortar from the chimney, I would think it would be on the other side of that 2x.

Water is amazing in its ability to find the path of least resistance. Sometimes it's extremely obvious, sometimes not. It is hard to see on a phone, but that flashing detail is kind of odd. I have to wonder if the shingles are properly overlapping the flashing and that there aren't spots where it is trapping the water, instead of shedding it. I would doubt it is related to the brick or the mortar, but if there is a path, water will find it.

Thanks for the info/thoughts.

apparently the flashing we're seeing is counter flashing and there is step flashing underneath it.  It was supposed to be underlayment, then ice/water shield, then step flashing, then counter flashing over top

the 2nd picture is from the top of the slope facing down - the first set of shingles is on top of the saddle, then the saddle is on top of the first/next row of shingles past it.

Thanks guys, I appreciate the additional thoughts.  I did several water tests with a hose yesterday with my wife on the roof with the hose (she's a keeper!) and me underneath watching for water.

we soaked from below the flashing line working our way up the slope, then worked just above the flashing and then one brick at a time (I was careful to wait at least 5 minutes after each test to see if any water that might have come through was delayed)


Results were surprising to say the least...  

Soaking where the flashing cuts into the brick and the first brick above it didn't result in any water coming through.  As soon as we started on the the 5th, 6th and 7th bricks above the flashing line the water really came through relatively quickly!

I suppose there might be something to the idea that it's coming through the masonry...

That's good news. If is step flashed under that then it probably has adequate coverage.




If it's your masonry it must be far worse than the images portray. For masonry to leak that fast there must be a path straight in. Usually, masonry takes a day or two to saturate and then weeps water. It's closer to capillary action but isn't dependent on gravity.

Repointing a chimney isn't a life changing event. It doesn't look like a huge chimney so it probably won't cost crazy money. You're the one with your eyes on it. If it's got significant cracks in the mortar joints it could stand to be repointed.

Research "Rilem tube test for masonry permeability"

My dad was pointed in this direction for a leak issue he was diagnosing from a local brick supplier. Turned out the brick needed sealed as the tube of water went through it in seconds. Everything looked normal and the results of the test shocked all involved as I recall.

I have the same color brick; that roof was the old one I had on my house. Good luck. I would call a roofer.

Good points - there are no obvious damaged points in the mortar, by there are some pin holes and hairline cracks where is separated from the bricks.  I've seen way worse without issue but perhaps it's enough in this case

Awesome, that's a great idea!