Help fixing a leak in laundry ceiling
 

For a few years now, whenever we have a heavy rain with a lot of wind, we get water leaking from our laundry room ceiling. In January I had Batterbee Roofing (the original roofer) over to have a look and while it wasn't obvious what might have caused it, they found and fixed a few areas around various vent pipes above the general vicinity of the laundry room that might have been responsible if they weren't 100% tightly sealed. Flash forward to earlier this week when we had very heavy, windy thunderstorms overnight. In the morning we had water on the laundry room floor again. So, it seems we didn't find the real cause back in January.

I climbed up in the attic space over the garage with a strong flashlight this morning to have a look. While I didn't see anything obvious like a puddle or water stains, I did see a duct of some sort that is sitting right over the laundry room ceiling. I am not sure, but I think it might be the vent for the water heater in the garage (although we don't actually have a water heater there, we have one of those on-demand Rinnai heaters in a different location). Anyway the duct in question travels a very long way from the point of origin all the way across the attic space and up towards the roof. The first picture attached shows that. The duct was apparently so long that it had to be split into two pieces and those two pieces are joined together and taped up right above the laundry room ceiling. The second picture attached shows that.

My theory is that when there is a heavy windy rainstorm, water enters the duct at the top and flows down the duct to this junction and sits there (because its a low point) and leaks through onto the ceiling below.

So anyway, my question is, who would I get to fix this? Before I found this I put a call into Batterbee to have them come back to have another look, but if this is the explanation, I don't think a roofer is what I need. Thoughts? Many thanks.
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bc

My first call would be to Mike Scott Plumbing 352-748-9111. Based on your post, this doesn't appear to be a job you relish taking on yourself. If in fact this vent stack was for a hot water heater, a plumber should be able to verify this, and suggest a fix or a remedy.

That being said, since the duct looks flexible, it appears to be for your dryer vent.

In the past, back in MA, I needed a vent for a stove hood. A roofer put in the vent on the roof but the person who installed the hood put in the duct work.

One time I had and electrician who put in a bath room vent and did all the work, vent in eave and duct, himself.

But in general my guess is that the roofer wouldn't put in the duct work. But when you talk to the roofer tell them what you have found... it's probably something they have seen before and what you will have to do to get it fixed. The vent on the roof should have something on to prevent rain from being blown in though.

But if water is collecting in the duct then just sealing it up would not fix the problem. It the duct was fully sealed it would eventually just fill up with water. If that duct was being used that could be a bigger problem than just a leak. Even if the duct wasn't being used a duct full of water would eventually cause an issue.

If you are using a tankless HW Heater why was the vent for your old HW Heater left behind? I would check to make sure this line is truly abandoned. If it is abandoned I would think any handy person should be able to remedy the situation.

++ Random thought: Is flexible duct work approved for HW Heater venting?

My guess is that water is getting in the duck through the roof vent. I had this problem and we changed the angle of the vents exhaust on the roof and that worked.

If the vent is not use let it drain into a dish pan at the point it leaks until you figure out the answer.

That looks like dryer vent duct. IMHO, if you can and are comfortable going on the roof, then look very carefully to see if the vent is allowing the rain in, if so you may need a new exterior vent. If this goes straight up, I would guess a cap came off sometime in the past.
Hope this helps.

This duct goes way up towards the back of the house and terminates a foot or so short of the area where the 3 round vent covers (if thats what you call them) are on the roof. The end of it is just hanging there in the air, not attached to anything. I'm no expert, but I really don't think that's how a dryer vent would work ...
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bc

No idea, we're not the original owners and the tankless hot water heater was here when we bought the house. I am guessing the duct is for the hot water heater because that's approximately where the other end of the duct appears to be headed. The dryer is just about right underneath where the two sections of duct are joined which is in the other direction from where the duct appears to be heading. That, plus my suspicion that a dryer vent duct wouldn't be left just hanging in space a foot below a roof vent ...
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bc

If your theory is correct, then it sounds like you need a roofer to fix a leak in the roof vent above the end of the duct at the other end of the house. The roofer you hired was at the wrong end of the house.

Run your dryer. Go up in the attic after a little while. You should feel additional heat, and the movement of the air through the vent. And you're right...a dryer vent shouldn't end in the attic, but you have no idea what the previous owner did.

As a picture is worth 1,000 words, in particular, the first attached picture is of the dryer vent. The duct I am talking about comes nowhere near this area. It hangs a foot or so below the circular vents in the second picture.
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bc

... and just for completeness, here's a view of the end of the duct that used to vent the hot water heater. It is interesting to note there's light coming through it. That would tend to support my suspicion that this is the leaking duct in question as it goes all the way up towards those circular vents and there is a lot of light up there.

So it appears that this is a roof issue after all and the previous repairs were in the wrong area. Is that the general consensus?
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bc

Yes. If your theory is correct, you need to get a roofer to fix a leak in one of those 4 roof vents. The duct has nothing to do with the problem. You could just remove the duct entirely, but you will still have a roof leak. The water would just show up somewhere else.

Exactly. And those "circular vents" are roof vents (your roof does not have a ridge vent system).

The vent in the ceiling where you see light shining through needs to be capped. It's a potential fire hazard. That is an easy fix.

I agree that if I removed the duct, the water would show up elsewhere, but I wouldn't go so far as saying the duct has nothing to do with the problem. I think it is whats ferrying the water to my laundry room ceiling. But that's the engineer in me being picayune, please forgive me for that ;-)
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bc

You'd just have a leak in a different part of the house

Agreed.
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bc

Sounds like you'll get it fixed. Good luck, and stay dry :)

OK, here is a real "out there" idea, what if there is a leak on one of the round roof vents, and the previous owner installed this tubing as a drain? Who knows, maybe they had a bucket at the other end of the vent! You should be able to test this idea with a volunteer and a hose. Go up in the attic with a really good flashlight, and have your volunteer aim the hose to rain on the vents, do not spray directly on them spray above and let the water fall on them like rain. Then look in the attic for water dripping.

Good luck, hope this helps.

Interesting thought but beyond my capabilities to test. My duct theory seems possible, but I'll admit, a bit unlikely. It seems there ought to be a simpler explanation, but I just can't come up with one. As an aside, how are gas hot water heaters supposed to be vented, anyway? Is it even possible that it what the duct is for?
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bc

Electric HW heaters are not vented. Natural Gas HW heaters are generally vented by a rigid vent pipe through the roof. It depends on the layout of your house, but as a rule, this is the norm. Tankless HW heaters require a larger diameter vent than standard tanks.

Not to belabor this, but I just took a much closer look at the duct in question and I now believe it is the venting duct for our gas furnace and not for the water heater. The two are fairly close together in the garage and there's lots of blown-in insulation in the attic covering everything so it was difficult to see exactly where the duct ended. The duct coming out of the furnace also looks like the right diameter, whereas the vent from the water heater is narrower and does appear to go straight up (we have gas for the dryer and heat so the now missing water heater was in all likelihood gas as well).
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bc

I would just look in the attic the next heavy rain storm and see if you can see where the water coming from. Even after the heavy rain you should see wetness. Especially how it’s getting down into the wash room.

I'll do that the next time that happens in the daytime. I'm not really a get up in the middle of the night person. :icon_wink:
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bc

One other question occurred to me. How are vents for gas furnaces supposed to be done, anyway?
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bc

Ok, nevermind about the furnace questions. I braved the attic one more time and had a much longer look at everything and its clear now the duct I was referring to is from the master bathroom, probably the exhaust fan vent.

I came to that conclusion after I observed that there's another identical duct at the other side of the house where the guest bath is that leads up to the same area. I simply hadn't noticed it before. I've attached a picture. Interestingly, the duct for the guest bath runs all the way up into the space just below the circular vent whereas the one for the master bath does not, it is just hanging in space several feet below. That should probably be fixed, but I can't imagine how anyone would get up in there to do that, especially with all the blown in insulation lying about. The master bath duct does pass over the area above the laundry ceiling and the place where the two sections of it is joined is right there, so it could still be involved I suppose.

On the other hand I also noticed this time that there's a large metal pipe in roughly the same area that leads up to the roof. It is the topmost gooseneck vent in the original picture (the lower one being the dryer vent). I'm not sure what that could be for. Could it be for the kitchen oven? That's right on the other side of the laundry room wall. I'm fairly certain that the roofer who was here in January worked on that area already, but perhaps it needs more attention. Maybe the vent just needs to be replaced. Upon further reflection, this seems somewhat more likely than the somewhat far-fetched master bath duct theory.

Though I was an engineer, I'm not the handyman type (bet you couldn't tell :1rotfl:).

We'll see what they say next week. Thanks for bearing with me ...
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bc

P.S. For the record, the second and third pictures are of the actual leak and the water on the floor after the storm earlier in the week. It's clearly not a huge leak, but has to be fixed regardless.

Ditto in our designer (when new). It took a year of roofer vs plumber arguments, but finally warranty stepped in and made someone come out and fix it. The vent angle needed to be changed. That solved the problem.

It looks like the builder ran the two bathroom exhaust ducts to the area just under the roof vents. This is probably okay, but, In the newer houses, they run the bathroom vent to the outside soffit and connect them to a hole that they cut into the soffit. I have even seen older houses that just vent the bathrooms into the attic space, and depend on evaporation to eliminate the moisture. But, it could be that your master bath duct has a low point above the laundry room, and the ceiling leak could be just an accumulation of moisture in the duct from the master bathroom exhaust fan that runs down to the low point and creates a leak. If that is the case, then you need to eliminate the low point by possibly installing a hanger to lift up the duct. This is just my opinion about what could be happening. Another solution could be to reroute the master bath duct to the nearest soffit location with hopefully a shorter run. Good luck.

One other point is that, if the bathroom exhaust duct is a long run, then the exhaust fan may not be strong enough to push the damp air to the end of the duct. In that case, all of the moisture from the bathroom will stay in the duct and run to the low point. This problem could be worse when it rains because of the increase in humidity in the attic.

The bathroom ceiling fans ducts are probably venting the the odors to the attic when you turn the fan on, I doubt the are attached to anything? In older home they don’t have ducts in attic the just vent up there.

Most building codes for quite a while now have required air to be vented outside. Venting to the attic or to the space between floors, which used to be done, seems like a recipe for growing mold, especially in Florida. I know when we added venting to our home in MA over 20 years ago we had to vent to the outside.

The Florida makes an exception for those big, whole house exhaust fans but not for smaller one like in a bathroom or over a stove.

CHAPTER 15 EXHAUST SYSTEMS
| 2017 Florida Building Code - Residential, Sixth Edition | ICC premiumACCESS

The bathroom exhaust runs are very long. They go from near the front of the home all the to the back and up near the roof vents. The master run is just hanging in space a few feet below the vent. The guest run goes up into the vent. I suspect the master one once did but broke loose at some point. While the master exhaust run does have a low point (and a taped up junction between two sections of duct) right above the laundry ceiling, the oven vent pipe is also in the same area. As best as I can tell, the dryer vent is nearby but a bit too far away from the area in question to be responsible. We'll see what the roofer says on Wednesday but at this point, unless he finds something obvious, I'm thinking of floating the idea of replacing the gooseneck vents for the oven vent and also the dryer vent just in case (maybe changing the angle as well as others have recommended). Plus, as we're expecting a lot of rain today, I might go up in the attic again and sit there watching for drips (now that sounds like fun, eh?). One thing complicating all this is that there's a foot or more of blown-in insulation covering everything up there.
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bc

Unfortunately the rain we're getting isn't heavy enough to trigger the problem (yet, anyway) but while I was up there looking around I decided that I really had to get over my trepidation at climbing deeper into the attic so I could reach the laundry ceiling area.

I took a broom with me to clear away the insulation so that I could see the other side of the laundry ceiling. I've attached some more pictures. The first is the oven vent from the outside. The second is the oven vent from the inside. Note the black stains along the beam above the red arrow and the strip of yellow sealant. The third is a closer view of that area and shows that the yellow sealant gets very thin right near the beam where the stains are. Finally, the fourth shows the attic side of the laundry ceiling and what looks like water stains centered around the seam in the ceiling drywall.

I suspect the thinness of the yellow sealant at the beam is probably responsible for the leak.

Comments?
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bc

Some parts of that stain in pic 3 look to be pretty dark... mold?

I didn't think that the flake board was sealed to the rafter... maybe glued though.

You can pick up a moisture meter pretty cheap at Amazon or probably home depot/lowes. That would tell you if that would had picked up mosture or it was just some kind of discoloration that was on the original wood. You could also use it to poke at other suspect places.

https://www.amazon.com/General-Tools...s%2C415&sr=8-3

Yes, probably mold from being wet on and off over a long period. There's no such stains anywhere else up there. At this point I'm going to leave it to the roofer. Going up there isn't good for my health. The risk of falling or mistakenly stepping onto the ceiling rather than a beam, not to mention the coughing fits I have after trying to move that blown in insulation around. It's time to apply (the late Jerry) Pournelle's law. If you don't know what you're doing, hire someone who does. :)
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bc

I met with the roofer this morning. He recommends replacing the vent with a modern, all one piece unit and re-shingling the area. He wasn't sure why that yellow sealant was used in that area. He said that's not usually done. Perhaps it was a previous attempt to stop the leak and not part of the original roof job. Anyway, we'll see how it goes.
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bc