why there are white lime trangle lines on walls aroud my chimney?

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peter101

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After winter I found there are white triangle lines on both side walls around my brick chimney. After raining for 1-2 hours, the brick wall on both side of the chimney will have a deep color triangle area larger and lower than white triangle lines. But, I have touched the deep color area and did not fell water on the brick after rainning lightly several hours.

When it does not rain, the deep color triangle area is fading out and can only see it 50 meter away. Till now, we have rain every week.

The saddle has no counter flash on top. And the chimney side flush is a long piece of metal, not stap flash. All seals are ok.

Please help me to find possible reasons?

Thank you.

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appears to be efflorescence & is probably caused by moisture behind the brickwork
 
Thank you for reply. Recently, I found one of my two downspouts was blocked at the bottom. I don't know if this is the reason to make water enter my brickwork around my chimney. The chimney is in the middle of my two downspouts.
 
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Doubtful, the gutter is probably 16" away from the wall. Missing mortar, improper wall flashing or failure of the crown of the chimney are my guess.
 
Doubtful, the gutter is probably 16" away from the wall. Missing mortar, improper wall flashing or failure of the crown of the chimney are my guess.

The outmost wall of my chimney is next the gutter. This part of wall will suck water if the gutter is full during the rain.

Before a rain, I have coverd the chimney from top to buttom with plastic, but I still get the dark color area on my side wall during the rain. One day After the rain, I open the plastic cover and found water on the chimney wall and plastic and the part which is 1 to 2 feet above the gutter has more water. I am sure that no rain enters the chimney during the rain.
 
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Check for wet insulation around the chimney in the attic.

After winter, I found some small gaps between the saddle and chimney wall. I patched the gaps with roof cement and seal all chimney flashs and the roof singles around the chimney. I still get the dark color area during the rain.

Then, in a sunny day I run tap water from the end point of the saddle to simulate a mild rain and keep water around the chimney in an area not more than 1 foot away the chimney. I did it 4 hours, but I can not reproduce the dark color area.
 
I have asked 5 contractors to check my problem. No body point out where is the problem. But, every one gives the same suggestion: cut the chimney under the roof and redo the roof. The chimney is for oil furnace and I changed to electric furnace 7 years ago.

But, my roof is only 15 years old and it is still ok even I have repaired 4 square feet blowing away singles. My roof size: 30 feet x 30 feet with slope.
 
Finding the source of water leaks is sometimes, at best, frustrating. My suggestion is to first rule out the obvious.

-Is the chimney properly step and counter flashed into the mortar joints?

-Do you have a "cricket" behind the chimney to divert water around the chimney chase?

-Are there any missing mud joints in the brick and if you run your finger along the joint does it release a lot of sand?

-Is the mud cap/crown/mortar cap in-tack without any cracks or voids?

From what I'm seeing you are getting water migration through the chimney above the gutter. The effervescences is all along the wall from the soffit down. The gutter is to far away from the wall to be the main issue.

I would try sealing the chase from the top down with a masonary sealer before you start tearing down structure. Fill in any cracks or voids because sealers won't bridge gaps.
 
Finding the source of water leaks is sometimes, at best, frustrating. My suggestion is to first rule out the obvious.

-Is the chimney properly step and counter flashed into the mortar joints?

reply: I can not see because the flash seal.

-Do you have a "cricket" behind the chimney to divert water around the chimney chase?

reply: yes, maybe I am wrong, I call it saddle.

-Are there any missing mud joints in the brick and if you run your finger along the joint does it release a lot of sand?

reply: no, I have fill all joints.

-Is the mud cap/crown/mortar cap in-tack without any cracks or voids?

reply: it is old, but without any cracks or voids on top surface.

From what I'm seeing you are getting water migration through the chimney above the gutter. The effervescences is all along the wall from the soffit down. The gutter is to far away from the wall to be the main issue.

I would try sealing the chase from the top down with a masonary sealer before you start tearing down structure. Fill in any cracks or voids because sealers won't bridge gaps.


I will try to cover the chimney again before a rain to make sure it is not chimney.
 
Did you get the part about the cricket, that is the roof shape behind the chimney to devert the water.
 
Did you get the part about the cricket, that is the roof shape behind the chimney to devert the water.

Yes, I have cricket (or: chimney saddle) behind the chimney and I found two 1" gaps between it and the chimney wall after winter and sealed it. Now, I have covered the whole chimney and the seals of chimney flashs with plastic, but I still has the deep color area after rain. The color is light than before I don't know if it is due to after one week of sunny day the water inside the wall has evaporated a lot or the covering the chimney.

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When you have the chimney wrapped up, put a sprinkler at the peak, you may just have a roof leak. Lately we have been working on a church that had a little roof leak last year and replaced that part of the roof. Someone noticed the stucco was a little discoloured so they checked it out and found some soft walls and hired a siding outfit to re and re the siding. The roof had been leaking for years and never showed inside.
We have been changing whole sections of walls that were held up with stucco and drywall. The best or I should say worsed was a 6"x48" beam 80 ft long the side has rotted in 1 1/2" all without showing inside. I am sure the engineers will tell us what to do with the beam right after the hart attack. We found ware the water was getting in and it traveled 40ft along the beam.
 
Neal makes a good recommendation to water test the area. Start by running water in the gutter, look for leak signs. Then move higher until you see evidence of water migration. Start low and slowly work your way up the chimney chase. I'd suggest using a hose with no nozzle instead of a sprinkler so you can localize the water flow...and be very careful on wet roof slopes or ladders.

Also, looking at the pic, i'll bet there is no flashing between the gutter and the backside of the chimney or kick-out flashing at the bottom of the brick sides. Can you get whoever tarped the chimney to take some pics from elevation?
 
Check for wet insulation around the chimney in the attic.

Now, I realize that I don't know what is wet insulation around the chimney because I thought the wet insulation was ice memberance stick around the chimney base and roof sheathing and now I think maybe I am wroung.

Could you please tell me in details about what is wet insulation around the chimney and how to verify it is good or not ?
 
Peter, are you seeing any water spotting on the ceiling of the room inside the house?

I did not find any water spot on ceillings inside the house and not under roof sheathing insdie the attic during rain (mild rain).

The roof only has plain roofing paper under the single and no ice memberance in the first 3 feet even I am located in very cold area.
 
You do need to check your attic insulation over that wall and around your chimney for water. You need to check it for twenty feet.
 
You do need to check your attic insulation over that wall and around your chimney for water. You need to check it for twenty feet.

Do you mean a water insulation and twenty feet horizontally?

What is the water insulation over the wall? If the wall is under my roof, does it have water insulation?

My house layers are as following: inside wall, air gap,black paper, wood fram, black paper, air gap, outside brick wall.

My bick chimney starts from my outside brick wall and I can not see the chimney and my outside brick wall inside the attic. I think either the chimney and the wall are outside my attic or their parts inside attic are short than the thermal insulation thickness.
 
Peter, what Neal was referring to was the insulation in the attic, if it is wet or if it has been wet it will have a crusty texture to it. Check on the horizontal, both side of the chimney. You will have to crawl over to the edge to check because of the slope of the roof. Also, can you see any water staining on the bottom of the roof decking where the chimney is located on the outside wall?
 
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