Water Marks appear on exterior wall

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Posted by: from Toronto
12/10/2012 at 8:43:30 PM


There are water marks that appear on one of the exterior walls. I contacted a roofing company but they weren't able to figure out the problem. Attached file you will see the water marks.

Could you tell me what is causing the probelm and how can I fix the issue?



water marks appear on exterior wall
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Date/Time12/10/2012 at 9:13:30 PM

Now depending if is a gable or a hip roof it could be cause improper ventilation which will cause inadaquat air flow from Moore vents into attic causing a condensation problem during certain times of the year.

We are from windsor, ontario.

I hope that was a help, there is no picture attached.

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Date/Time12/10/2012 at 9:45:40 PM

There may not be any breathers in the mortar joints in between the brick which also causes that. Go up close to the brick and see if there are any on the bottom and midway up the wall.

Where is the home located?

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Date/Time12/10/2012 at 9:59:23 PM

It definatley is a condensation problem. I have looked close on the picture and I don't see any vents in the mortar joints.

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Date/Time12/10/2012 at 10:13:58 PM

There are no vents in the mortar joints which is common problem. This can be repaired.


Michael Sorrenti

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Date/Time12/10/2012 at 11:33:20 PM

Most likely your roof flashing is not proper designed and installed. Need to have a site visit to see the probem in order to provide a plan of attack.



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McInnis Contracting in Belleville
Date/Time12/10/2012 at 11:35:17 PM

Hi Marco,

Its Mike o/o of McInnis Contracting, I have looked at the picture you have provided and by looking at that I would say you do not have a roofing issue their, it appears to me their may be a plumbing issue, one of the pipes on the inside wall, that would probably be running on a joice at exactly around that spot, is leaking and causing the water spots outside of the residence.

I am going to assume this is a two-storey unit, you have the main level, and then at the second floor there would be a pipe leaking their.

That would be my opinion of this situation as a water leak from a roof would not appear on your house like that, especially that far down from the edge of the roof.

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Date/Time12/10/2012 at 11:46:47 PM

I would be surprised to see plumbing pipes on the outside wall, and if so I would only assume it would visa le from the inside of building, but apron further investigation you can tell from picture there is improper venting on soffit, you have one over a 30 foot span.

Looks like you need on on site inspection.

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Date/Time12/11/2012 at 4:11:55 AM

The water stains are at floor level on the second storey therefore I assume they are caused by a leaking pipe or even by a leaking toilet. What kind of room is located on this wall and since when do you notice the stains? Just recently?


3D-Tile-Design - Bertram Tasch

Maple Ridge, BC (Greater Vancouver)

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Date/Time12/11/2012 at 8:06:20 AM


Did not receive attatchment. Sorry i cannot help.

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Date/Time12/11/2012 at 1:18:23 PM

It's not your roof. It's not your soffit. Everything seems to be in proper order. There isn't a problem with your ventilation on your soffit either, that's bogus.

Your problem lay in mortar joints or more likely a plumbing condensation issue.

Do u have a bathroom located near the area shown?

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David from Chetco Homes in Fort Erie
Date/Time12/12/2012 at 11:37:59 AM

Didn't see the picture but by the sounds of it, It could be condensation that will form in the attic if it is not vented properly. It will show up more in the spring.

Best I can come up with from here.

Good luck

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Date/Time12/24/2012 at 1:27:48 PM

Hi Guys,

This is all hypothetical and without actually getting a camera in behind the inside wall,you will not know.

But I tend to agree with one poster who said it could be plumbing pipes from your bathroom..If There is a bathroom up there I would bet you have the tub,sink and toilet all with plumbing on the outside wall. The weather is colder now so there would be condensation. The only way I could see you getting so much is that the insulation is no longer there properly installed behind the pipes on the outside wall.

You will need to remove a piece of drywall at one of the condensation spots to investigate.

Not much more you can do.



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