Since masonry isn’t my area of specialty, I figured I’d pose this question here… in the attached picture, if you look at the bottom of the chimney there are bricks with their faces still intact (darker shaded brick). However, the majority of the bricks on the chimney seem to have lost their face. A few questions:
1. Is this what is referred to as “brick rot”?
2. Can I just seal the bricks with a sealer to prevent further decay, or is this a tear down to the roof and replace job? (Of course some pointing will be needed if sealing is an option.)
3. What causes this? Is this just poor brick manufacturing (i.e. improper firing, etc)?
This chimney is on a house in SE Michigan, built in 1942…
Replies
looks more like erosion...
how long ya keeping the house...
tear it down, rebuild and fix several problems and be done with it......
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
got a top view at the flues and one of the roof flashing line???
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Doesn't look like there's much flashing there. By rotting, do you mean the black areas? That looks like it's stained. The brick at the upper corner seems to have had something pounded into it, just like the other one with the face popped out. If there are areas where the face popped out with no holes, that's called spalling and is usually caused by the brick taking on moisture and then freezing or being cold and having direct sunlight heat it with the cycle being repeated over the years. My house was built in 1946 and also has the orange-red brick, but mine have the scratched face. I have some staining and spalling, but not much. I've inspected it and the rest is sound."I cut this piece four times and it's still too short."
Edited 12/6/2004 10:17 am ET by highfigh
top front brick looks mechanically damaged..
hard call on the flashing...
lots of leach thru...
why all therust...
pointing has about had it by the looks of things...
I think 3 colors of brick where originally used for asthectics...
and the kid that raked the leaves missed some...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
can barely make out the cracked cap around those flue liners. Water coming in there would keep the backside of the brick damp, freeze thaw would surely cause spalling/efflorescense/etc there. You fix the top, point whats needed and replace any brick that are "gone" and you should be alright.
Remodeling Contractor just outside the Glass City.
Quittin' Time
I agree with Calvin.
Looks like the problems originated at the flue /cap. That needs to be corrected, or any repair you do is wasted effort.
IIRC FHB or JLC had recent article on chimney caps. It pointed out the masons generally make the caps out of mortar, and it is not the correct material for a cap.
Dave
The rust is probably from an old sheeet metal flue cap and if you look at the leaves, they're across the street so I think you're barking up the wrong tree. I wonder if the nails (or whatever the metal that was driven into the brick and mortar joints) may have been for hanging lights or some other kind of decorations.
"I cut this piece four times and it's still too short."
we have a handle on this...
so how much we gonna charge Burpnboy???
I'm in WVA right now...
old antenna perhaps....
metal embed rusting....
look again...
I say the kid missed some....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Maybe some kid missed some, but there's a curb between the house with the chimney we're looking at and the leaves. How do you know it wasn't vandals?
"I cut this piece four times and it's still too short."
or a nieghbor getting rid of his...
I think the kid was just lazy...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Thanks everybody for the responses. Some replies from my side...
No, unfortunately I don't have more pictures. I think highfigh nailed the rust being from an old flue cap. Nails... I'm sure were probably from an old TV antenna as IMERC responded. This is based on the neighbor across the street still having his hanging precariously from the chimney.
At a minimum I was planning on redoing the flashing, repointing, and redoing the top cap. I'm not going to be in the house for too much longer, which is why I'd prefer avoiding a complete rebuild.
By "rot", I'm referring to something I had read in a masonry book a while back. It referred to the facing coming off the brick as "brick rot", and I believe they attibuted it to poor firing of the brick at the time of manufacture.
The colors... no, one color is what it should be... the darker red. That's the shade of the rest of the house. The black is years of dirt, and the light red... my worn out brick.
Oh, yes, the leaves are across the street. Probably were the same ones that were on my yard a couple days earlier. ;-) Mother Nature can sure be a time saver with that "wind" thing...
DaveRicheson... what is the correct material for chimney caps? Just curious, because I've read lots of different things...
Depending on where the materials for the brick came from, sometimes it's more porous, like mine, and the "brick rot" or spalling happens. Sometimes, because of whatever is in the air, the outer surface will be more crumbly and dusty. Efflourescence is a leaching of minerals in the mortar and this problem can be remedied by washing the area with a solution of salt peter(Potasssium Chloride, if memory serves) dissolved in water. Yes, THAT salt peter.I have seen concrete and limestone caps, mostly (yours looks like limestone). The mortar I have seen was only for filling gaps and creating runoff. Your cap looks OK, just has rust on it and a couple of cracks in the mortar, so you could take care of that if you repoint it.
"I cut this piece four times and it's still too short."
metal cap from the SM shop....
seal and repoint the brick....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
When the face pops off, it's called spalling.
Sometimes results from repointing older softer bricks with a hard portland-rich mortar.
It's often easier to just rebuild from the roofline up. By the time you get into replacing individual bricks, and pulling out old mortar, you may end up with more net time into it. Plus the work is more pleasant.
I agree with Calvin: seal (caulk with urethane) the cracks in the cap and repoint under the lower corbelled level. I think the dampness in the darker brick is mainly coming in through there. (see attached pic - I reduced its size and threw in some arrows to where I see problems.)And check the rest of the cap and chimney mass for other areas to fix, then seal the whole thing with a masonry sealer.I don't know about yours, but my church isn't a hotel for the holy, it's a hospital for sinners
Sojourners: Christians for Justice and Peace
I can think of several possible causes of this problem, and I don't know nuttin' compared to lots of folks here.
Spalling brick can be due to poor quality brick, moisture getting into the brick and freezing, a chemical reaction due to the mortar, a chemical reaction due to acids in the flue gasses, thermal cycling due to hot flue gasses, etc.
In your case I suspect that several of these effects are active. The worst of the spalling seems to be in the middle, on the part that projects. Probably it works out that rainwater tends to concentrate down that path, and, from the stains I see on top, it appears that some sort of chemical reaction is at work there as the water runs down.
In the upper left you can see cracking that is fairly typical for that location. That's probably due to frost action, after water leaks down into the brick from above.
All in all, though, the chimney doesn't appear to be in that bad of shape. I'm guessing that this is about a 50-year-old chimney, and it doesn't appear to be unusually weathered or in any danger of rapid deterioration. Your problems appear to be more cosmetic than structural. (Can't totally evaluate the soundness of the mortar from the picture, though.)
Mainly, you want to prevent moisture from leaking down inside. This mostly means caulking or mortaring any cracks in the top. Also, repair any mortar that has eroded to the point where it leaves much of a recess, as these recesses allow moisture to enter.
geez, come on guys.
no, the cap is not OK.
it is several beautiful pieces of slab limestone that were capped with a mortar wash.
the mortar wash is gone.
period.
kaput.
it is the cause of all the damage.
the limestone is fine. if you want to do the quick and easy fix ( which you shouldn't ) you can strip the mortar wash and redo it with the same thing. then you can grind and caulk the limestone joints with polyurethane caulk. repoint and repair the spalled bricks.
the problem with the wash is that it will never bond properly to the limestone and there is nothing you can do to make it stick.
what really should happen is the top of the chimney should get the masonry wash as a base for a custom metal cap. the cap can be done in lead or copper.
the difference here is that the masonry wash by itself will only last another 5 years. the next owner will not maintain it and the already weakened chimney will end up falling apart.
on the other hand, the metal cap could give you another 50 years.
actually, it would be the next owner.....
carpenter in transition