New house - all galvanized exhaust vents are leaking (buy, drywall)

[djslakor]

Wondering if anyone has experience with this one ...

I noticed water dripping onto the firebox of my gas fireplace over the weekend. No water was dripping into the fireplace, but I could hear it landing on top of the fire place.

As a precaution, I got up in my attic this morning and observed the 2 other galvanized exhaust vents on my roof are also leaking. I saw water trickling down both pipes at a slow pace. Luckily, one of them has an elbow directly above a pretty large HVAC drip pan, so that one is a freebie (very little water had collected after the last 3 days of rain). The hot water exhaust above my garage, however, was dripping water on the dry wall ceiling at about 1 drip per 10 seconds or so. I'm guessing I'll have to replace that dry wall.

I was standing directly under the flashing for those pipes and noted the water was not coming in around the cut out in the decking. The water was running directly down the pipe. Would this indicate the problem is the caulking around the storm collar? Where the vent slides through the flashing piece? That's all I can imagine. Otherwise it would have to be a cracked flashing or a terrible vent design. If rain was entering in the vent, it wouldn't be coming down the side of the vent pipe, though. So i'm thinking it must be bad caulking or cracks in the external pipe.

Anyone have more useful tips? I can't get up there in the pouring rain to re-caulk it at the moment

[Bp25]

How new is new house? If you are still within warranty (usually 1 year), call your builder's warranty department. It's probably just bad calking of the "hat" that sits on the top of the inverted funnel shaped flushing, not sure what it's called.

[djslakor]

My warranty ended 2 weeks ago.

Is it normal for caulk to fail after a couple years?

[Katana49]

I think you are probably correct if the water is dripping down the pipe. Depending on the slope of your roof, I could see that possibly there may be a hole in the flashing, I've seen some builders use a nail gun on those things and it can leak from the nail hole and drip down.


In the meantime, get a pan and try to keep any more water from making it to drywall, you may be fine by allowing it to dry out. I'd also take pictures and video to document this if you are still under warranty, especially if a drywall/paint repair will be needed.

[djslakor]

Originally Posted by Katana49

I think you are probably correct if the water is dripping down the pipe. Depending on the slope of your roof, I could see that possibly there may be a hole in the flashing, I've seen some builders use a nail gun on those things and it can leak from the nail hole and drip down.


In the meantime, get a pan and try to keep any more water from making it to drywall, you may be fine by allowing it to dry out. I'd also take pictures and video to document this if you are still under warranty, especially if a drywall/paint repair will be needed.

I would think a nail gun issue would cause a leak where the flashing slides up under the siding, and i'd be able to see the water coming in there rather than down the pipe.

[panacea1982]

Probably exhaust vents have cracks. It happened to us. Two exhaust vents.

[djslakor]

Originally Posted by panacea1982

Probably exhaust vents have cracks. It happened to us. Two exhaust vents.

I considered that. The house was built 1.5 years ago in the 400k range, so it would be something else if the vents they used were so cheap they already cracked. How old were yours?

[turf3]

The correct way to prevent leaks around roof penetrations is to use a flashed vent, installed correctly. Caulking is not involved.

You need to have a roofer up there to inspect each of the roof penetrations, determine what are the details of what's wrong, and fix it.

I doubt very much whether the quality of the hardware is involved, but I could be wrong; I think it's far more likely that some hammerhead did something wrong in the installation.

As far as how long one can expect a roof penetration not to leak, I don't think I have ever had a flashed vent fail within the lifetime of the rest of the roof (20-40 years).

[Rakin]

If your warranty only ended 2 weeks ago the builder should take care of the problem.

Let me rephrase that... A good builder will take care of the problem. A crappy builder might not.

Did you buy from a good builder or a crappy builder?

[panacea1982]

Originally Posted by djslakor

I considered that. The house was built 1.5 years ago in the 400k range, so it would be something else if the vents they used were so cheap they already cracked. How old were yours?

the house was built less than 1 year ago.