Rain inside chimney

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I've searched and read a few posts regarding occasional rain entering the chimney, but I haven't seen much with regard to the implications.

My cathedral ceiling install is done with the exception of connecting the class A to stovepipe. The sheetrock ceiling hasn't been patched yet, so I can see clearance around the protruding support box from inside the living space. There are no leaks around the support box or in the support box.

During a rain, water was clearly dripping down the inside of the class A. Since it's currently not connected to anything inside, I can look directly up the chimney and see the rain drops invading. It's clearly not much water at all. I would imagine that if there were several days of uninterrupted rain, I would probably find a small puddle in the stove (once all is connected).

I'm using Selkirk SuperVent model JSC with the deluxe rain cap. I am certain the rain cap is correctly installed (it's a no-brainer), and the class A is perfectly level.

Is a little rain invasion expected/normal? If not, what should I do?

What are the implications? (It seems obvious that, during heavy rain, I may have a problem getting a fire started---probably more smoke).

Thanks!
 
humpin iron said:
should be no rain getting in, prob a bad seam on the chimney
Thanks for the reply.

I don't see how it could be the vertical seam because it would mean the rain is penetrating the exterior hull, the fibrous insulation inside the pipe and then into the interior hull. Visually inspecting the inside of the pipe, I see no focal point of entry, just droplets lining the interior of the pipe. The only horizontal seam is the joint, and there is only one exposed joint. The joint is secured with a support band. Additionally, the droplets start above said joint.

I really feel the rain is penetrating via the rain cap. By design, there is a double-stepped pitched roof (I assume this is the traditional design of all rain caps) This design allows a straight down rain to trail away from the opening. However, any wind, and this measure is circumvented. Also, heavier raindrops "splatter" as they strike the cap allowing stray droplets to make their way into the chimney.

So, you're saying there should absolutely be no way for the rain to penetrate?

I'm using the deluxe rain cap Selkirk sells for this particular model of chimney. Should I be looking for an alternate rain cap?
 
When it's raining sideways you may get some down the pipe, not much you can do.
 
You really shouldn't have much water coming down the inside of the pipe unless it was a heavy rain with very high winds. I have the Supervent deluxe rain cap and Supervent stainless chimney. I initially had water leaking down mine and out the ceiling support box and was positive it was the rain cap. Turned out water was getting in an outside seam and coming out at the support box. It seems to be a all too common with Supervent chimney. A bead of silicone down the seams fixed mine.

I have a feeling that is where your water is coming from. (It is leaking out at the bottom, right?) In my opinion it would be a good idea to go ahead and silicone the seams anyway since it all too common with the Supervent chimney.
 
whats a little rain among friends eh? sounds like mostly splatter and driven rain, and thats not all that bad. you would have to use one mighty rain cap to keep all the rain out. Guess you could go with three "T's" up top and two rain caps. Dont laugh, seems to be a common setup in ol' dowtown colorado springs.
 
Nic36 said:
...(It is leaking out at the bottom, right?)

Not sure what you mean by that. When I looked up the barrel of the chimney, droplets were scattered diffusely throughout the interior of the pipe. Following your logic, the rain penetrated the outer hull, the the fibrous lining, then finally the inner hull. Seems far fetched, but I'm no expert and that's why I asked for opinion.

Nic36 said:
...In my opinion it would be a good idea to go ahead and silicone the seams anyway since it all too common with the Supervent chimney.

I respect your opinion, and I will do just that. The silicone can't hurt.
 
i think a picture of the outside of your chimney would be worth 1000 words here. 0r several pictures for that matter!

pen
 
Its funny Im about to install and do the same thing your doing, put the cathedral ceiling support box and class A chimney through the roof and leave it open will I work on the hearth. Then once I set the stove tie it in from there. And I was wondering the same thing, if it rains am I gonna get some water back through the pipe. Let us know if the silicone worked out
 
I guess I should have worded my question better. I meant to ask if the rainwater was making it's way all the way down the pipe and dripping on the floor. Rain will come in the chimney some, especially when it is windy. I noticed raindrops inside my chimney before I hooked up the stove. But, the rainwater never made it down far. The cap will keep it from coming in much and it will simply dry on the walls of the chimney.

But, if you are having it drip on the floor, it may be coming in at the seams.

So, if you are just seeing raindrops clinging to inside of the chimney two or three feet below the cap, that is normal. So, no worries there.
 
humpin iron said:
should be no rain getting in, prob a bad seam on the chimney

Nic36 said:
...I have the Supervent deluxe rain cap and Supervent stainless chimney. I initially had water leaking down mine and out the ceiling support box and was positive it was the rain cap. Turned out water was getting in an outside seam and coming out at the support box. It seems to be a all too common with Supervent chimney. A bead of silicone down the seams fixed mine.

I have a feeling that is where your water is coming from. (It is leaking out at the bottom, right?) In my opinion it would be a good idea to go ahead and silicone the seams anyway since it all too common with the Supervent chimney.

Mystery solved. The presence of water droplets on the inner hull was a red herring. They weren't making it all the way down the stove pipe. Since I've connected the stove pipe, no rain has entered the stove itself. A long steady rain revealed the culprit. A drop of water was seen trailing down the exterior of the exposed class A at a rate of about 1 drop a minute. I was intending to wait for a clear day, but it was eating at me. I went on the roof and carefully inspected the seams on the class A. I now concede that humpin iron and Nic36 were correct. One seam had a wider gap than the others. I put a bead of silicone in all the exposed seams and the dripping immediately ceased.

Thank you all so very much. Now I'm water tight!
 
Glad you solved the problem. Now enjoy the heat!
 
Backwoods Savage said:
Glad you solved the problem. Now enjoy the heat!

Thanks. But it will be a while before we can fire it up. It's just not cold enough for long enough right now in East Texas. We had a frost about 4 days ago, but the afternoon temps got up into the 70's. I only ran the central heat for a couple hours that morning to knock the chill off. The part I don't like about central heat is that in order to adequately heat the living room/kitchen (one open area) with cathedral ceiling, it warms the bedrooms, which have standard 9' ceilings, too much. I'd rather not heat the bedrooms. Hopefully the wood stove will improve that situation.
 
Okay. One of these days we'll start a nice cold north wind to blow on you so you can enjoy that wood heat! ;-)
 
Backwoods Savage said:
Okay. One of these days we'll start a nice cold north wind to blow on you so you can enjoy that wood heat! ;-)
its coming.
 
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