What is this?

[Midpack]

There’s some light water damage on the ceiling about 6” from the wall in one of our upstairs bedrooms and this much darker (series of) spots a little over 2 feet in. They’re very much in lines across the ceiling, but visually exactly perpendicular to the ceiling joists? There’s no plumbing or ductwork up there. The only thing I can think of that runs perpendicular to the joists might be a deck plywood seam well above.

There are truly a lot of clever people here so I though I’d ask before I cover or remove all the clothes in our master closet, crawl thru our attic on my hands and knees, fill my nose with fiberglass and risk putting a foot through the ceiling in multiple places. Of course the access point is in the master closet as far from the bedroom in question as possible...

[braumeister]

How old is your roof?

[Midpack]

Quote:

Originally Posted by braumeister How old is your roof?

Only about 10 years, and it was done by the most reputable residential roofer in our little berg, been in business for almost 40 years. Premium architectural shingles, etc.

[pb4uski]

It sort of looks like a leak stain.

Joists would typically be parallel or perpendicular to the outside walls and it looks like the line of the stain is neither. Correct?

[Texas Proud]

Looks to me like you have a leak and the water is coming through on the seam of the sheet rock... IOW, not related to where the water is starting... but where it is running too....

[target2019]

Vent pipe grommet bad?

[Cobra9777]

Quote:

Originally Posted by target2019 Vent pipe grommet bad?

That would be my guess as well. Look for roof penetrations in that general area. I've had water stains in a line on the ceiling that resulted from water dribbling as it ran down a rafter... until it hit something, and then you get the larger spot.

[braumeister]

Quote:

Originally Posted by Midpack I’d ask before I cover or remove all the clothes in our master closet, crawl thru our attic on my hands and knees, fill my nose with fiberglass and risk putting a foot through the ceiling in multiple places.

I can't understand why you would deprive yourself of such an adventure.

Go for it! You might find any number of interesting things up there.

[pb4uski]

Quote:

Originally Posted by Cobra9777 That would be my guess as well. Look for roof penetrations in that general area. I've had water stains in a line on the ceiling that resulted from water dribbling as it ran down a rafter... until it hit something, and then you get the larger spot.

That might explain why it is a straight line but is not parallel or perpendicular to the joists... the vent pipe probably runs above the joists and then leaking water runs down the pipe and drips off onto the drywall ceiling and through it making the stain. That is my hypothesis anyway.

[Midpack]

Quote:

Originally Posted by pb4uski It sort of looks like a leak stain. Joists would typically be parallel or perpendicular to the outside walls and it looks like the line of the stain is neither. Correct?

The stains run perpendicular to the ceiling joists.

Quote:

Originally Posted by Texas Proud Looks to me like you have a leak and the water is coming through on the seam of the sheet rock... IOW, not related to where the water is starting... but where it is running too....

Hadn’t thought of that, makes sense.

Quote:

Originally Posted by target2019 Vent pipe grommet bad?

Hadn’t thought of that either. It’s not the furnace, dryer, range or drain vent, so by process of elimination it’s our hot water heater vent (pic below, same window as the pic in post #1).

Quote:

Originally Posted by braumeister I can't understand why you would deprive yourself of such an adventure. Go for it! You might find any number of interesting things up there.

I’ll give you $20 and lunch if you want to do it, KY isn’t that far.

Thanks all, at least I have some ideas what/where to look, was just hoping it would be something easier, though I knew it wasn’t likely. I expect to see stains running down from the vent penetration on the deck plywood or roof joists inside and/or evidence in the loose fill insulation. May go up when it’s raining. Can’t wait...

[Janet H]

Another choice here besides a leak might be condensation above the ceiling typically caused by plugged roof or soffit vents. I had this happen a few years ago after some blown in insulation shifted a bit. Soffit vents were obstructed and during heating season condensation built up and dripped off joists. The damage was slow and the stains were linear. The solution was to add ridge vents and was not terrifically expensive although the water stains had to be managed..

[pb4uski]

Quote:

Originally Posted by Midpack ..... before I cover or remove all the clothes in our master closet, crawl thru our attic on my hands and knees, fill my nose with fiberglass and risk putting a foot through the ceiling in multiple places. Of course the access point is in the master closet as far from the bedroom in question as possible...

Can't wait to see the video.

[Midpack]

Quote:

Originally Posted by Janet H Another choice here besides a leak might be condensation above the ceiling typically caused by plugged roof or soffit vents. I had this happen a few years ago after some blown in insulation shifted a bit. Soffit vents were obstructed and during heating season condensation built up and dripped off joists. The damage was slow and the stains were linear. The solution was to add ridge vents and was not terrifically expensive although the water stains had to be managed..

I’ll check that too. We have ridge vents but still could be the problem. The soffit vents are 31 years old and I’m sure the builder used the cheapest he could find.

[happy2bretired]

That looks like my ceiling. I had frost in my attic this past winter and needed more ventilation installed. IMG_0044.jpg

[W2R]

Quote:

Originally Posted by Midpack There are truly a lot of clever people here so I though I’d ask before I cover or remove all the clothes in our master closet, crawl thru our attic on my hands and knees, fill my nose with fiberglass and risk putting a foot through the ceiling in multiple places. Of course the access point is in the master closet as far from the bedroom in question as possible...

Midpack, you're not a poor man having a hard time making ends meet (to say the very least). You can't fool us - - you've posted enough about yourself here that we have a general idea of your financial wherewithall. We know you are living the good life that you have earned over the years.

Instead of venturing up there yourself, why not do a big favor to a handyman by hiring him to go up there and get it taken care of. You can afford it and he would be so happy to have the work. Consider it as a semi-charitable act if that helps. Also, consider how much nicer your day would be without going through what you described above. This could be a win-win situation.

[pb4uski]

^^^ great idea. That and if he puts his foot through the drywall ceiling (which I did while working on our first house.. my mind has a recording of DW's scream when it happened very near to her) then he'll be responsible for fixing it.

[Janet H]

Call a roofer since you are most likely going to have to hire their services to fix what ever is wrong anyway. They can diagnose and fix....

[Midpack]

Quote:

Originally Posted by Janet H Call a roofer since you are most likely going to have to hire their services to fix what ever is wrong anyway. They can diagnose and fix....

Great minds...I had come to that conclusion last night. I’ll just have all the roof vent/penetrations checked and fixed while we’re at it. Planning to sell the house in about a year too, all the more reason to get the issue resolved.

[target2019]

Quote:

Originally Posted by Midpack The stains run perpendicular to the ceiling joists. Hadn’t thought of that, makes sense. Hadn’t thought of that either. It’s not the furnace, dryer, range or drain vent, so by process of elimination it’s our hot water heater vent (pic below, same window as the pic in post #1). I’ll give you $20 and lunch if you want to do it, KY isn’t that far. Thanks all, at least I have some ideas what/where to look, was just hoping it would be something easier, though I knew it wasn’t likely. I expect to see stains running down from the vent penetration on the deck plywood or roof joists inside and/or evidence in the loose fill insulation. May go up when it’s raining. Can’t wait...

Need you to get up there for a closer look!
Cold air comes in the large attic end eave vent. Then some kind of roof vent (high up on the roof) to let hot air escape. Then you have a much larger gas flue.

Hot and cold air coming together. Frost is very possible in the extremes we have.

[BrianB]

A neighbor had similar looking stains in their second floor ceiling. There were no water pipes up there, and no vents or flues that could have led to the moisture. It turned out to be condensation as others have commented.

This article / blog post by a home inspector describes it pretty well, with causes and some ideas for solutions.

Frost in attics: Why it's there and how to fix it - StarTribune.com