I had a leaky fireplace chimney and it turned out
that was water was actually going thru the brick
of the chimney. A guy came out and sealed the brick
with some brush-on stuff that is clear and undetectably
from looking at my chimney from the ground.
He is long gone now and the stuff is still working.
What is that stuff he coated it with?
That is exactly what I thought. I fought and fought with
my roofing contractor over this and was certain that bad flashing
was to blame. He told me that it was my brick and that water
went right throught it. He proved it to me by taking my
water hose up on the roof, trickling it over the brick on the
side of the chimney while I was in the attic watching it come
right on through. He further proved it to me by hiring that guy
I mentioned who put the "sealant" on which, beleive it or not,
did cure the leak. I was as suprised by this as anyone but have
since told many people about who reply 'oh, ya, everyone knows
that brick does not stop water'
And thats why I want to know what the stuff is. I'd
coat my whole house with it so long as its relatively invisible
and it doesnt make it look like my house is coated with something.
Because if it leaked through my chimney, maybe its leaking
somewhere else that I dont know about.... yet!
mark Ransley wrote:
Chimneys are subjected to all the weather and deteriorate from the
inside and outside , the freeze thaw cycle that happens daily here in
the winter is hard on them. Brick doesnt leak like that unless it is
possibly bad. Id still say its your mortar ,you only need a hardly
visible hairline crack to allow in water. Get a few tuckpointers to
look at your house some with alot of experiance, Ive repaired alot of
chimneys and damage may be hidden by a tuckpointing job. Leaks will
turn the internal mortar to sand. Ive taken out one inch good face
mortar and found the next foot, or through the complete chimney is like
sand. Because of years of leaking and bad tuckpointing jobs. How old is
your house, how long have you owned it
Thanks for your replies, you sound very knowledgable
on this subject. The house is 5 years old and in Dallas so
although we have had freezes, they are few and far between.
Yes, the mortar could be the cause of the leak and not the
actual brick - I really dont know.
What is tuckpointing?
I didnt have a leak that I know of until I had a new roof
put on (because of hail damage). That is why I figured it
was the roof or flashing that was causing the leak. the roof
man argued with me about this, then I stood in the attic while
he ran the hose water over the brick on the outside. I couldnt
tell where exactly the leak was but could see water comming into
the attic. The so-called sealant stopped the leak - I dont know
how though but it is just as likely that it sealed the mortar
as it sealed the brick.
mark Ransley wrote:
The more I read that the more I think it was the flashing. If he was
pouring water on the brick, would it not also go over the flashing, which if
defective would leak? I would think it would take some time for the water
to go through the brick.
Tuckpointing is repairing the mortar between the bricks.
If it was the flashing, then applying a coating of
something by brush to the brick would not have solved
the problem - which it did. (right?) I know - I thought
it was flashing at first too. The point at which the
water was applied to the brick, did cause the water to
run down the chimney and over some flashing. But the
Flashing at that point seemed to be, by physical examination,
Joseph Meehan wrote:
You mention roofer ,did you get a new roof. Did your roofer put on new
flashing, or leave the old. A 5 year old chimney without the freezes we
have in the midwest wont have internal problems as we get. I was also
refering to 70 yr old chimneys, so you problem is either the cap , the
mortar or flashing. A hairline mortar crack will let in water, one that
doesnt look bad but maybe a thin sharp knife can slip into . Still an
experienced chimney man is best, call a few people and get them up on
the chimney and get a few estimates. Problems like this can be real hard
to find , and you will get different answers, but keep looking.
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Keep the whole world singing. . .
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