# Vinyl sided chimney on side of house - rotting OSB



## Tom Struble (Dec 29, 2008)

rfleege said:


> We have a vinyl sided chimney on the side of the house about 6 feet or so from the top of the roof. It is cut into the overhang of the roof about 2 feet and then 2 feet extend past the rake edge of the roof. So the back (top) side of the chimney is about 2 feet wide on the roof and then 2 feet off the roof. I just noticed a wet spot from the basement on the subfloor and investigated further. I went up to the roof and noticed gaps in the siding where the water ran right off the chimney and into and behind the siding. There's a good chunk of rotted OSB on the chimney chase now.
> 
> I will have a contractor come out next week to look at it but what I am asking is to see what the best method of correcting this so it doesn't happen again once the chimney chase wall is repaired. How can you direct water so it doesn't hit the chimney side wall?
> 
> Thanks.


ooo something like this perhaps?

http://www.bendtek.com/Kick_Out_Diverter.htm


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## Michael Thomas (Jan 27, 2008)

The key is correct flashing at the uphill side of the chimney - it should be flashed like a conventional chimney part way down a sloping roof, only flashed so as to prevent water from running down the rake at the uphill intersection of the chimney and the edge of the roof. The easiest way to do this is to flash so as to redirect all the water hitting the uphill side of the chimney around the chimney at the side of the chimney opposite the rake. Unfortunately don't have a picture of this type of flashing, and could not find one on the net.


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## Michael Thomas (Jan 27, 2008)

tomstruble said:


> ooo something like this perhaps?
> 
> http://www.bendtek.com/Kick_Out_Diverter.htm


We has a similar discussion here a while back: http://www.diychatroom.com/f49/reflashing-chimney-60854/

A conventional kickout flashing will work well at an chimney penetrating a *eave*:

Kick out flashings reduce leaks at the junctions of chimneys and roof eaves - Paragon Home Inspections Chicago/Morton Grove/Evanston

but will not work where the uphill side of a chimney partially penetrates a roof at the *rake* as water runs off the roof at the roof/chimney and down rake, chimney and wall below.

I've seen three methods of flashing this junction:

1) A sort of "single sided cricket" which directs water running down the roof diagonally toward the side of the chimney opposite the rake.

2) A diverter flashing which extends diagonally down the roof above the chimney, sloping down the roof from the rake toward the edge of the chimney opposite the rake.

3) Various types of "flashing" (usually ad hoc) which attempt to protect the rake and areas below it as water ruins off the rake side of the chimney.

I do not have pictures of any of them, however.


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## Tom Struble (Dec 29, 2008)

yes after re reading i see your point,my mistake,i think

we need a pic of your chimney


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## rfleege (Nov 19, 2010)

Here's an image. You can kind of see the siding stained where the water flowed. The house is 23 yrs old, we bought it in February, had a re-roof in April, and just noticed this now. Based on the completely black, flaking OSB and evidence of previous attempts at caulking this spot, it has been a problem for years. There's got to be a way to divert water around to the left (down the roof) and away from the rake side.


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## Tom Struble (Dec 29, 2008)

like Mr. Thomas says a cricket is probably your best bet


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## johnk (May 1, 2007)

No cricket needed there.Just proper flashing


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## Michael Thomas (Jan 27, 2008)

Well... The question is, what is "proper flashing" at that location? You can flash the uphill side to the chimney with a conventional chimney head flashing, but if you allow water to flow out over the edge of the rake, how - exactly - do you flash rake board, chimney and wall?


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## johnk (May 1, 2007)

There should not be an issue with water running down siding,if the siding is installed right.A backpan extended past the rake 2-3" with a slight slope inwards should do the trick.I've done many that are exactly like that without any issues or complaints for that matter.


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## johnk (May 1, 2007)

Not to go on and on about it but it is a very simple detail for any real roofer.If done right also you will have no more run-off at the rakes at that point than anywhere else.


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## rfleege (Nov 19, 2010)

Just to confirm, the whole backpan should have a slight angle inward, forcing the water to run towards the middle of the roof, or just have a bend inward for the overhanging 2-3" over the rake?


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## Michael Thomas (Jan 27, 2008)

johnk said:


> There should not be an issue with water running down siding,if the siding is installed right.A backpan extended past the rake 2-3" with a slight slope inwards should do the trick.I've done many that are exactly like that without any issues or complaints for that matter.


Are you referring to a bend at the end of the head flashing (basepan) to from a sort of reverse kick out flashing (see attached) or actually forming the head flashing so as to be wider (further from the chimney) at the rake side of the chimney?


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## Slyfox (Jun 13, 2008)

You install regular L 'head wall flashing' at the face 'front lower portion' of the chimney.

Install step flashing's up the side, letting the last piece of flashing & shingle wrap the top corner.

Install L 'backpan' flashing 'at the top'.
The back pan should be cut to go atleast 10" up the chimney,
atleast 12" on to the roof sheathing,
atleast 3" past the inside corner 'facing the roof',
atleast 2' past the overhang of shingles on outer corner 'rake side' and
have a slight slope to it making the inside corner the high point, thus sloping to the rake.

The back pan will set over top of the siding panel that hits roof level,
than under the panels of siding from there up.
This allows the water to run on top of the siding rather than behind it.


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## jmiller (Nov 19, 2010)

Slyfox said:


> Install L 'backpan' flashing 'at the top'.
> The back pan should be cut to go atleast 10" up the chimney,
> atleast 12" on to the roof sheathing,
> atleast 3" past the inside corner 'facing the roof',
> ...


All the rainwater should be diverted into a gutter at the eave, not off the side of the house. With the pan pitched the wrong way you'll also have a gap where the last pc of step flashing meets the pan.

I'm also having a bit of trouble picturing how the j channel that runs up the fascia and along the pan would integrate with the back pan if it was partially covering a pc of siding or even sticking out further than the fascia. I can see it working with traditional siding but maybe i'm having a brain fart with the j channel.

I've always pitched mine to run back onto the roof and bent the rake edge to lap over the fascia. The rake side is a tricky intersection to waterproof so I try to make the water go the other way, which is a much easier corner to flash properly (you can't have ice/water on your fascia board), and prevents staining.


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## Michael Thomas (Jan 27, 2008)

Slyfox said:


> You install regular L 'head wall flashing' at the face 'front lower portion' of the chimney.
> 
> Install step flashing's up the side, letting the last piece of flashing & shingle wrap the top corner.
> 
> ...


Thanks

1) To make certai I understand: you are sloping the entire "backpan" flashing relative to the chimney, with the "rake" side of the flashing further up the roof?

2) If so are you:

A. Bringing the backpan slightly further out from the chimney at the top of rake side of the flashing?

-or-

B. Installing the entire width of the top of the flashing flush with the chimney, and pulling the bottom of the flashing out away from the chimney at it's lower edge on the rake side?


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## MJW (Feb 7, 2006)

What's needed here is a Contractor, not just a roofer. I'll put my life on it that the siding is leaking, not the roof. Seen it many times just like the picture shows. Some siders think vinyl siding alone keeps water out. 

A ton of work like this in the near future fellow Contractors. Too many slop jobs in the past 15-20 years.


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## Michael Thomas (Jan 27, 2008)

MJW said:


> What's needed here is a Contractor, not just a roofer. I'll put my life on it that the siding is leaking, not the roof. Seen it many times just like the picture shows. Some siders think vinyl siding alone keeps water out.
> 
> A ton of work like this in the near future fellow Contractors. Too many slop jobs in the past 15-20 years.



No question attention will have to be paid to the siding and flashing detailing at that junction - for starters, there may not even be a water resistant barrier (Tyvek or similar) behind the siding. And at a minimum using slyfox's technique (where a portion of the flashing will be under the siding) the WRB will have to be carefully detailed where it is slit to fit over the vertical leg of the flashing so as to prevent water entry.

Such detailing is why I'm so skeptical that this is an "easy" problem to solve if "you "just know how" - I'm wiling to bet that when everyone has had their say and we all agree on a "best" design (if we do), that it will incorporate at least some details that each of us overlooked in our original proposed solutions.


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## Michael Thomas (Jan 27, 2008)

Here's a closer look at the intersection:


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## Slyfox (Jun 13, 2008)

jmiller said:


> All the rainwater should be diverted into a gutter at the eave, not off the side of the house. With the pan pitched the wrong way you'll also have a gap where the last pc of step flashing meets the pan.
> 
> I'm also having a bit of trouble picturing how the j channel that runs up the fascia and along the pan would integrate with the back pan if it was partially covering a pc of siding or even sticking out further than the fascia. I can see it working with traditional siding but maybe i'm having a brain fart with the j channel.
> 
> I've always pitched mine to run back onto the roof and bent the rake edge to lap over the fascia. The rake side is a tricky intersection to waterproof so I try to make the water go the other way, which is a much easier corner to flash properly (you can't have ice/water on your fascia board), and prevents staining.


You can create the slope in either direction by munipilation of the pans bend and do so with both sides setting tightly against the chimney wall.
I always divert water off the roof in the shortest most direct route.

Your J-channel can be cut to form the needed coverage where the roof flashing & siding meet.


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## Slyfox (Jun 13, 2008)

Michael Thomas said:


> No question attention will have to be paid to the siding and flashing detailing at that junction - for starters, there may not even be a water resistant barrier (Tyvek or similar) behind the siding. And at a minimum using slyfox's technique (where a portion of the flashing will be under the siding) the WRB will have to be carefully detailed where it is slit to fit over the vertical leg of the flashing so as to prevent water entry.
> 
> Such detailing is why I'm so skeptical that this is an "easy" problem to solve if "you "just know how" - I'm wiling to bet that when everyone has had their say and we all agree on a "best" design (if we do), that it will incorporate at least some details that each of us overlooked in our original proposed solutions.



I have two laborers currently working with me, one with roughly four years experience and one with three years.
Either of them could roof & flash that chimney.

My point, you need someone familiar with both roofing & siding applications and your problem will be solved, it's really not as difficult a fix as your thinking.


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## Tom Struble (Dec 29, 2008)

may not even be coming from there:no:


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## jmiller (Nov 19, 2010)

Slyfox said:


> You can create the slope in either direction by munipilation of the pans bend and do so with both sides setting tightly against the chimney wall.
> I always divert water off the roof in the shortest most direct route.


I know HOW to make it run out the rake edge and all down the siding, just not why. 

On second thought, I don't know how either, since it would create the gap between step and back pan dealy (to quote palin) I mentioned earlier. 


The most direct route in any flat pan behind a chimney straddling the rake edge would be split 50/50 between running it towards the rake or inside corner. A more direct route than gutters would be right onto the ground, but that's not right. :whistling2:


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## johnk (May 1, 2007)

My preference would be to keep the water on the roof.You would only need the slightest slope considering the short width of the chimney.A simple water test would tell you exactly where your peskey leak is coming from.Either way,it is a very simple fix.Even if you had to redo siding,flashings,shingles,etc.


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## johnk (May 1, 2007)

Have you checked b-vent flashing,pan,etc uptop?


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## Slyfox (Jun 13, 2008)

jmiller said:


> I know HOW to make it run out the rake edge and all down the siding, just not why.
> 
> On second thought, I don't know how either, since it would create the gap between step and back pan dealy (to quote palin) I mentioned earlier.
> 
> ...


I divert it off the rake side rather than onto the roof for a couple reasons.
1. pushing the minor amount of water hitting that small of an area out onto the roof into the heavier run off will/doe's cause a swirling effect and pushes it back into the sides of the chimney.
2. the amount of water hitting the back of that chimney is going to be such a small amount it won't hurt anything running off the side,
assuming the siding is installed properly.

No matter which way you divert the water you have to create a slope,
it's a very mild slope in this case but a slope just the same and you have to do it with out creating a space between the pan and the wall of the chimney.
I do that with a double crimp bend on one side and a single standard bend on the other.


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## ClimateControl (Nov 20, 2010)

*L- Flash it*

Deff L flash it. Make an L with metal flashing, Position the large side of the L under the shigles, then run the other side of the L up the chimney. Of course, caulk and seal:thumbsup:


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## SDC (Feb 18, 2009)

rfleege said:


> We have a vinyl sided chimney on the side of the house about 6 feet or so from the top of the roof. It is cut into the overhang of the roof about 2 feet and then 2 feet extend past the rake edge of the roof. So the back (top) side of the chimney is about 2 feet wide on the roof and then 2 feet off the roof. I just noticed a wet spot from the basement on the subfloor and investigated further. I went up to the roof and noticed gaps in the siding where the water ran right off the chimney and into and behind the siding. There's a good chunk of rotted OSB on the chimney chase now.
> 
> I will have a contractor come out next week to look at it but what I am asking is to see what the best method of correcting this so it doesn't happen again once the chimney chase wall is repaired. How can you direct water so it doesn't hit the chimney side wall?
> 
> Thanks.


If you are having a contractor come out to look, why don't you wait to see what he suggests for a fix, after all, he will be looking at it. Although it may be an easy fix, we are only guessing not seeing firsthand. 
I would find it difficult to tell you the best approach to fixing water and leaking issues without looking.


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## Michael Thomas (Jan 27, 2008)

Problem, is I see contractors "fix" such problems incorrectly all the time.


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## MJW (Feb 7, 2006)

Michael Thomas said:


> Problem, is I see contractors "fix" such problems incorrectly all the time.


Yep, that's when we usually get a call. :wink:


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## SDC (Feb 18, 2009)

Michael Thomas said:


> Problem, is I see contractors "fix" such problems incorrectly all the time.



I too have seen and know so called contractors who cannot fix the problem as well. All I am saying is, if you are having someone come out to look, I would think THAT person would be better informed on how to handle the issue that people on-line. 
How can you trust people here??
I have seen (not this thread BTW) lots of people in this chatroom give awful advise, as I'm sure many of you have too.
If the contractor he calls cannot fix it...he should be calling someone else...

Here is a nice example of a home that had a flashing detail leak....but the vinyl siding held up perfectly...:laughing:


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## jmiller (Nov 19, 2010)

SDC said:


> Here is a nice example of a home that had a flashing detail leak....but the vinyl siding held up perfectly...:laughing:


Were gutters the missing flashing detail?


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## Michael Thomas (Jan 27, 2008)

jmiller said:


> Were gutters the missing flashing detail?



Looks to me like missing gutters plus missing kick out flashings:










This detail is for a kick out at a wall, but the use at a chimney is the similar, see here for more information:

”Roof” leaks caused by missing kick out flashings at chimneys can cause "wall" leaks below- Paragon Home Inspections and Thermal Imaging Chicago


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## jmiller (Nov 19, 2010)

It's good that you point them out to your customers. A lot of inspectors miss it.

In SDC's pics it looks like the water ran all the way down the outside of the siding until it hit the j channel at the bottom, which was probably pitched towards the rotted wall on both sides.


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## SDC (Feb 18, 2009)

jmiller said:


> It's good that you point them out to your customers. A lot of inspectors miss it.
> 
> In SDC's pics it looks like the water ran all the way down the outside of the siding until it hit the j channel at the bottom, which was probably pitched towards the rotted wall on both sides.



Correct, you hit it right on the head...:thumbsup: water was running down the chase siding, going into the "J" channel at the bottom of the chimney chase. It was then running right towards the house. This house was built in 1997, not that old, with proper flashing and details like above, this would not have happened.


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## Michael Thomas (Jan 27, 2008)

SDC said:


> ...with proper flashing and details like above, this would not have happened.


Private message sent.


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## Slyfox (Jun 13, 2008)

SDC said:


> I too have seen and know so called contractors who cannot fix the problem as well. All I am saying is, if you are having someone come out to look, I would think THAT person would be better informed on how to handle the issue that people on-line.
> How can you trust people here??
> I have seen (not this thread BTW) lots of people in this chatroom give awful advise, as I'm sure many of you have too.
> If the contractor he calls cannot fix it...he should be calling someone else...
> ...


I have seen many in this forum and others giving really pi** poor advise.
That shouldn't stop us from giving our opinions tho, with everything said here on this subject the OP will know what questions to ask when he meets the roofer who shows up and be able to better decide if that roofer really knows what he is talking about.

BTW, The pics show poor flashing "maybe the roofers, maybe the siders" the gutters or lack there of don't cause leaks like that.


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## SDC (Feb 18, 2009)

Slyfox said:


> BTW, The pics show poor flashing "maybe the roofers, maybe the siders" the gutters or lack there of don't cause leaks like that.


Siders all the way...:furious:

It all starts at the bottom of the chase......I agree gutters don't cause leaks at all. Faulty installs, clogs, etc. can cause leaks, not products.:thumbsup:


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## SDC (Feb 18, 2009)

BTW
I have not seen the OP back here, I hope all of this will help...:thumbsup:


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## Michael Thomas (Jan 27, 2008)

IMO, that's a "combination of ingredients problem" - the siding install guaranteed that water would enter the exterior wall wall at the bottom of the chase even absent the roof runoff above, and the lack of gutters and the missing kick out flashing guaranteed a high concentration of water from roof runoff was present to worsen the problem.


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## Michael Thomas (Jan 27, 2008)

To go back a step, SDC's example is a good illustration of why I'm skeptical that when a chimney penetrates a rake, the chimney's flashings should direct water over the rake rather than back toward the roof side of the chimney. 

We know that real-world, even at new construction, wall cladding details will usually be imperfect if not blatantly incorrect, and that as a result at least some water will be entering behind the water resistant barriers and flashings details.

And we know that at older buildings, there will often have been a series of modifications (siding and window installs, additions, wall penetrations for dryer and bath exhaust fans and the like, etc.) which compromise the original wall water-control provisions, often in ways we can't visually assess without removing portions of the cladding and/or trim. 

We also know that the investigation and and correction of many of these defects will usually be outside of the scope of the work being performed during a re-roof or even the installation of a roof at new construction. For example, in SDC's examples few roofers are going to be pulling off siding to investigate its installation, except perhaps for a small area at the roof, chimney junction itself - even if they are aware of the potential problems, or even strongly suspect they are present, convincing homeowners to pay for the investigation and repair of such problems will be somewhere between difficult and impossible).

So the the questions confronting someone installing a roof (if they even bother to ask it) is not "Is water getting into the walls?", it's "How much water is getting in, and how fast is it deteriorating the materials it reaches?". 

And real-world, given the quality of the actual work by others we see every day, the answer usually is "If it's not too much water, and it's not creating too much damage" (i.e. there is only minor deterioration, and it's going to take decades to cause problems), then "given the nature of the beast, that's about the best we can expect, but let's at least try not to make it any _worse_...".

And from that perspective, why would a roofer want to direct substantial quantities of water down a wall of unknown but likely imperfect water-resistance, when there is the alternative of sending it down the roof to be eventually conducted away from the rest of the structure by an appropriate roof drainage system?


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## jmiller (Nov 19, 2010)

There are hundreds of places that would leak like that if they were exposed the amount of water directed down that wall. Gutter guys would have probably sealed gutter to vinyl and gone a long way towards preventing this.


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## Tom Struble (Dec 29, 2008)

good call Mr.Miller,vinyl siding can handle a surprising amount of water intrusion,but even it has its limits

if that was wood or fiber cement,i'd imagine the damage would be much worse if installed with the same level of expertise

side wall water protection should not depend on one system for ''waterproofing'',but should be attacked with a multi layered approach


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## kwikfishron (Mar 11, 2010)

Michael Thomas said:


> even if they are aware of the potential problems, or even strongly suspect they are present, convincing homeowners to pay for the investigation and repair of such problems will be somewhere between difficult and impossible).


I disagree, I don’t think I’ve ever had a customer that didn’t want the root cause of the problem detected and resolved. What’s the point of a new roof or siding if it’s still going to leak. Although not always the case, more times than not it is a simple flashing or wb detail that is the problem and correcting it is usually a small additional charge compared the cost of the job.


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## MJW (Feb 7, 2006)

Or we could just keep our mouths shut and let people get what they pay for. That would be better for all of us, right?


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## Michael Thomas (Jan 27, 2008)

kwikfishron said:


> I disagree, I don’t think I’ve ever had a customer that didn’t want the root cause of the problem detected and resolved. What’s the point of a new roof or siding if it’s still going to leak. Although not always the case, more times than not it is a simple flashing or wb detail that is the problem and correcting it is usually a small additional charge compared the cost of the job.


If someone is aware that there _*is*_ a problem, yes, they want it resolved - for example it's likely that SDC pulled that siding because there was evidence of water intrusion at the interior of the wall under the chase, not because his customer was concerned about the evidence of concentrated water flow down the chase at the exterior of the siding.

I'm speaking instead to the situation where:

1) A construction detail (in this case the penetration of a rake by an exterior chimney) predisposes the soffit and the wall below it to moisture damage, and the likelihood of damage depends in large part on factors (for example, the presence or absence of a water resistant barrier under the vinyl siding, and its correct or incorrect installation, the provisions for controlled drainage at the bottom of the chase, etc.) that cannot be fully determined by visual examination of the undisturbed exterior cladding.

-and-

2) There is no evidence that such damage is occurring (yet, at least).

In such situations it can be very difficult or impossible for a roofer called in (for example) to do a re-roof to get customers to pay for investigation of a problem that *might* be present, and/or to get them to pay for "industry best practice" instead of "locally accepted practice" on the strength of the roofer's opinion that better (and more expensive) workmanship *might* prevent problems down the road - this is just a fact of life, and its one reason we see so many poor roofing jobs and the damage that results.

Please note that I'm on the side of the angles in this - I've referred hundreds of thousands of dollars in business to competent contractors and a major part of my job is to educate my clients about the enormous difference between vendors: to help them spec work so that they can evaluate what's being proposed, to help educate vendors about current industry best practice, to perform progress inspections to insure that work is being done to the agreed standards, and then to follow up to determine what works best (and worse) over time.

So if you are a contractor trying to convince a potential customer to pay for quality work, I'm your best friend, there to help the customer understand why the work should be done properly.

However, what I provide is an opinion.

I hope it's an informed opinion, and one that I can defend based on documented industry best practice - but as everyone who performs or evaluates such work knows both industry sources and highly competent vendors sometimes have very different opinions about what works best (or, at all), and in some cases the industry consensus of opinion changes over time.

And that's one reason I hang out in places like this (as well as vendor oriented boards): do-it-yourselves come here with a real-world problems, and people propose real-world solutions - some better, some worse, some I've seen, and some that are new to me.

It's interesting and useful largely because they sometimes challenge opinions I already have.

In this case, it seems "obvious" to me based on experience that if you have the choice of directing water above a chimney back onto the roof rather than over the rake, you should keep concentrated water flows off the soffit and walls below on general principle.

An experienced roofer disagrees.

I want to know why - this is a case of "please convince me me I'm wrong. Because if so, I've learned something useful..."


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## Michael Thomas (Jan 27, 2008)

MJW said:


> Or we could just keep our mouths shut and let people get what they pay for. That would be better for all of us, right?


See the post above.


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## Slyfox (Jun 13, 2008)

LOL, this thread has gone crazy, no wonder the OP hasn't commented in awhile.

The fix for both those chimney leak situations, which are detectable upon inspection with out tearing anything apart, is not worthy such a long drawn out discussion.
As far as diverting water off a rake from behind a 26" wide chimney pan,
your talking about such a minor amount of water it is absolutely harmless, both mechanically and aesthetically.


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## jmiller (Nov 19, 2010)

Slyfox said:


> LOL, this thread has gone crazy, no wonder the OP hasn't commented in awhile.


Actually it's still completely on topic. Last sentence from the original post: "How can you direct water so it doesn't hit the chimney side wall?"

Good question.



> The fix for both those chimney leak situations, which are detectable upon inspection with out tearing anything apart, is not worthy such a long drawn out discussion.


IIRC here was only one chimney leak. The other was siding. The siding might not have leaked if excess water hadn't been coming down the wall (lack of gutters), but it begs the question why ever direct roof runoff down a wall if given a choice. 



> As far as diverting water off a rake from behind a 26" wide chimney pan,
> your talking about such a minor amount of water it is absolutely harmless, both mechanically and aesthetically.


Granted, 26" doesn't sound like a lot. Code here however says a 30" + chimney requires a cricket.


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## jmiller (Nov 19, 2010)

Slyfox, from one contractor to another:

I would trust my top corner chimney flashing to handle 10x the water/ice/snow that it will ever see, but I have no idea how well the siding is waterproofed. If you make the pan pitch towards the rake you just bought the warranty on a wall of siding IMO. Why do that if you trust your chimney flashing?


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## Tom Struble (Dec 29, 2008)

Slyfox said:


> LOL, this thread has gone crazy, no wonder the OP hasn't commented in awhile.
> 
> The fix for both those chimney leak situations, which are detectable upon inspection with out tearing anything apart, is not worthy such a long drawn out discussion.
> As far as diverting water off a rake from behind a 26" wide chimney pan,
> your talking about such a minor amount of water it is absolutely harmless, both mechanically and aesthetically.


 

i'm having fun:thumbup:


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## Slyfox (Jun 13, 2008)

jmiller said:


> Actually it's still completely on topic. Last sentence from the original post: "How can you direct water so it doesn't hit the chimney side wall?"
> 
> Good question.
> 
> ...


It's the same here, but the 26" was just a number that pops up on those styles regularly, I doubt that one is even that wide.

You guys are over thinking the slope I'm putting toward the rake.
The slope is extremely minor that it's not going to create a valley offect.
No matter what you do with the pan in that situation your going to have water running off that rake, the only way you can stop that is to not install a pan and go with a half cricket or something of that nature.


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## Slyfox (Jun 13, 2008)

jmiller said:


> Actually it's still completely on topic. Last sentence from the original post: "How can you direct water so it doesn't hit the chimney side wall?"
> 
> Good question.
> 
> ...


It's the same here, but the 26" was just a number that pops up on those styles regularly, I doubt that one is even that wide.

You guys are over thinking the slope I'm putting toward the rake.
The slope is extremely minor that it's not going to create a valley offect.
No matter what you do with the pan in that situation your going to have water running off that rake, the only way you can stop that is to not install a pan and go with a half cricket or something of that nature.


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## Slyfox (Jun 13, 2008)

Sorry for the double post, not sure if it's my connection or DIY's but all I did was edited my post with color to show my response.


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## jmiller (Nov 19, 2010)

Slyfox said:


> It's the same here, but the 26" was just a number that pops up on those styles regularly, I doubt that one is even that wide.
> 
> You guys are over thinking the slope I'm putting toward the rake.
> The slope is extremely minor that it's not going to create a valley offect.
> No matter what you do with the pan in that situation your going to have water running off that rake, the only way you can stop that is to not install a pan and go with a half cricket or something of that nature.


I agree, a slight slope isn't going to keep all water from going to the rake edge anyway. 

One other option mentioned earlier was an L flashing tucked under the shingles two or three courses above the chimney that REALLY pushes water inward enough to keep it off the rake (and can extend past the inside chimney corner as well if it's of unknown quality). 

The above detail is even listed in the Velux install manual for a custom flashed horizontally installed skylight, so it's not really as hackish as it sounds. I never cared for them myself, unless they were part of the gutter system, and not sure if it would satisfy code officials as a cricket, but it would work for the OP.


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## Michael Thomas (Jan 27, 2008)

Slyfox said:


> No matter what you do with the pan in that situation your going to have water running off that rake, the only way you can stop that is to not install a pan and go with a half cricket or something of that nature.


And that's - ideally - what I think should be there.


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