Some questions about the best way to deal with a leaky chimney / roof
area. I'm hoping there are some knowledgeable masons /
home-owners out there with good ideas...
I have an 11-year old 2-story colonial with a chimney at one end of the
house, slightly off-center. For the past 8 years, there have been
on-again, off-again problems with water in the attic where the edge of
the roof meets the chimney. Not dripping water, but wet plywood
causing visible stains, especially after a long rain. The attic is
well-ventilated, so it's not interior moisture.
I've had various roofers and masons try various fixes over the years:
1 - Had the counterflashing re-done (cut out the old with a diamond
saw, put in new counterflashing). It's not interleaved with the
shingles, which I think may be a problem.
2 - Had the chimney sealed about 4 years ago with a siloxane compound
3 - Had caulking applied between the chimney and the siding of the
4 - Had a metal chimney cap put on above the flues.
5 - Had the shingles and step flashing around the chimney re-done, 3
times (!). The first 2 times, the folks turned out to be not so great.
They used a ton of silicone, even under the shingles, and basically
made a mess of things.
The 3rd roofer, recently, was pretty good; seemed a very
experienced, competent fellow. He ripped up the shingles; put a new
ice-and-water barrier in that area and around the chimney (making sure
to overlap it with the bottom course of shingles); and put in new step
flashing. This helped -- but even after a moderate rain, there was
still a 1" wet spot in the attic, a little above where the bottom
corner of the chimney meets the house.
And here are the recent recommendations I've had from various masons /
1 - Re-do the flashing (again).
2 - Re-seal the chimney (again) (with ChimneySaver, or a Umaco
3 - Put a thicker concrete crown on top of the chimney, and extend the
flues a couple inches above the crown (right now, they're flush with
the top of what looks like a fairly thin mortar crown).
4 - Tear down and re-build the chimney above the roof-line; do
selective re-pointing; and then do #1-3 above. (This option would cost
about $3200 - $4200.)
So (finally), here are my questions:
1 - In general... which of the above sounds like a reasonable approach?
Any other thoughts?
2 - Does the price on option #4 sound right? It seems a lot of
money... but none of the other fixes have worked.
3 - On the masonry web sites I've read, the usual recommendation is to
extend a concrete crown a couple inches past the edge of the brick; to
put an expansion joint around the flues; and ideally to flash the
flues. All the masons I've talked with, even the experienced,
competent-seeming ones, dismiss these ideas. How important is it to do
4 - Near the top of the chimney, it's corbeled out and back again in a
"beehive" (i.e., 3 successive courses of brick out, then 3 back, then
up to the crown). One mason would prefer to re-build it without
corbeling into a beehive. Does it matter, from a water absorption
5 - How important is it that the flues don't extend past the crown
At least in this area, it seems that there aren't that many masons who
(a) are experienced and competent, and (b) return phone calls and show
up. I've found one or two (I think), but before spending even more $$$
on this issue, I'd like to get the wisdom of folks out there (even
after having read a lot of the past threads on chimneys & masonry).