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I've replaced these valleys already on other jobs. There was not a wet spot anywhere. The reason for covering it is that any metal is always colder than the shingles. This creates more ice. The same way a gutter helmet does.

There isn't a water channel on a weaved valley, is there?

If it rains hard enough, a water channel just creates more of an area to get behind the shingles.

You do have a point, but we have been doing this since 2000 and never had a problem. Like I said, some of those jobs have been replaced in 2006 and now some in 2008 and 2009. Didn't find a leak on any of them done this way. Only found leaks on weaves and cut valleys.
 

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I have to add that we have seen leaks that are created by leaving the 1" to 2" open on the valley tin. This was only in certain areas where pine needles get stuck in the valley and start collecting. This channeled water under the shingles. That was the first reason we went to the method of running the bleeder shingle tight to the valley V.
 

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Curmudgeon
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Go up on the roof after your next rain and carefully lift a few of those valley shingles touching the metal and you'll find water under them because there's no water flow channel between the center off the valley and the end of the shingles.
Any thing that holds water 'even in small amounts' will decrease the life span of the shingle and any metal including copper will dry rot if left exposed to setting water.
Even a 1" channel on either side of center is acceptable,1 1/2" at the top and 2" at the bottom is better.

Post a pic of the same area in 5 years and you'll see what I mean.
:thumbsup:
 

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I have to add that we have seen leaks that are created by leaving the 1" to 2" open on the valley tin. This was only in certain areas where pine needles get stuck in the valley and start collecting. This channeled water under the shingles. That was the first reason we went to the method of running the bleeder shingle tight to the valley V.
I have seen leaks in every type of valley, some times human error, some times material problems such as self sealers failing due to debris being forced/trapped between the shingles and many times due to debris building up and causing water to damn and run off to the sides.

Leaks do not always make it into the interior of the structure but if you look at the materials as your tearing them off for re-roofing you can see the signs of damning/mis-directed water.

Weaved valley's do have a water channel, it's the point in which each course crosses the other, the more uniform the crossing the longer they will hold up to the weather because the water is constantly being pulled to the center of the valley rather than allowing it to run freely.
The constant pull to the center keeps it running off faster.
Just like a closed cut, the more uniform the cut side the better the water is directed to the center, if you cut to close and cover the center you will end up with water traveling sideways under the cut.

I'm not trying to be a smart butt or a know it all or even voicing a personal opinion, it's a mathematical/gravitational fact, time tested and proven.
 

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Curmudgeon
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"You must become the rain,"
Grasshoppah. :clap::laughing:
 
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Tell me why gravity is not present in the picture I showed..........

I have looked at what you are talking about. Every single roof we have done, I have done personally. I do know what to look for. You can't tell me that my valley leaks because I know that it doesn't. I'm not the only one that uses this method. If there was one single problem, I'm sure we would have heard about it by now.
 

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Roofer
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With a quality install they usually won't leak because the fasteners are held back and the metal is lapped properly, I really was not trying to suggest other wise.
The problem that even a quality install can not stop is the same with weaved valley issues which is the valley will not hold it's look as well/long because the water takes longer to run off thus the shingles will curl and eventually even burn up faster in that style of valley 'just like weaved valleys do'.

Water will not run off as quickly in that style of valley is what I was referring to as being a fact.
 

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Tell me why gravity is not present in the picture I showed..........

I have looked at what you are talking about. Every single roof we have done, I have done personally. I do know what to look for. You can't tell me that my valley leaks because I know that it doesn't. I'm not the only one that uses this method. If there was one single problem, I'm sure we would have heard about it by now.

Dude, really tho, running shingles on valley metal..... over kill i think....That stuffs like almost 40.00 a sheet here...and running the shingles that close to the w? I think thats a water trap and debris trap. From experience.... it's always been wetter under shingles done like that.....but looks really good.... i just dont see where years and years of roofing has gotten changed overnight. I dont think many people use this method youre using, but if it's dry inside the house... thta's what roofs are all about when it's said and done. There's more than one way to skin a cat... I just cant say i agree with that way...
 

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Like I said, with low pitches and leaving the 1" to 2" open in the valley we have seen problems....Mainly in areas with alot of pine needles and small tree branches. We used to snap a line from 1" to 1 1/2" and run the shingles on that, but since tearing off some of our jobs due to hail, we seen small trickles of dirt, and water get pushed under the runner shingle. Still never leaked, but there was potential.

Yes, the valley's were up to as high as $40, but have come down lately. 24" valley is code here, although if you use no valley at all, the code isn't enforced.
 

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Like I said, with low pitches and leaving the 1" to 2" open in the valley we have seen problems....Mainly in areas with alot of pine needles and small tree branches. We used to snap a line from 1" to 1 1/2" and run the shingles on that, but since tearing off some of our jobs due to hail, we seen small trickles of dirt, and water get pushed under the runner shingle. Still never leaked, but there was potential.

Yes, the valley's were up to as high as $40, but have come down lately. 24" valley is code here, although if you use no valley at all, the code isn't enforced.
What happens when the pine needles build up in your style of valley?
Pine needles, twigs, leaves, etc., are still going to end up in the valley and will still get caught up in the shingles and along the hump of the metal, what than?
Water will still be redirected once such build ups occur.

You can not stop debris issues in valleys or along other penetrations such as walls, etc., you can only maintain the issues by having the roof cleaned of such debris from time to time.
 

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Sly, what can I say.....Haven't had a problem since. You continuing to find a flaw for this method confuses me. I know you have more experience than that. I could understand this viewpoint from a salesman, but you are an installer just like myself.

I can understand the comments about waste or being called lazy....whatever. 2 man crew/business...can't call me lazy. Fact is, it's faster, more protection, and it doesn't leak.

The only thing I can think of that maybe some don't understand that the tar strip is on the back of these shingles. In other parts of the country, they may be still on the front. In that case, this method wouldn't work.

Sorry if I sound disrespectful. I don't mean to come off that way.... In our small area, we HAVE to do things that work. If not, we don't get referrals for jobs.
 

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I didn't see anything disrespectful in your comments nor was/am I upset about anything you had to say.
I'm not trying to nic pic your procedure of running the shingles the way your picture showed, I am just trying to let you know it's not a new method and it's not flawless.
I tried that method first with wood shakes and later with tiles because of the same reasons you mention with the 'standard' open cut method and it did not change anything in the long run, just the short term.

I have never met any of the roofers in this forum real world, but just through communications in here there are a few roofers that I have respect for just based on their forum post and you are one of those roofers.
So trust me when I say I am not trying to be disrespectful to you either.

If I could type as fast as I think "two finger typer" people would understand me a lot better.:blink:
 

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Thanks for the compliment.

Never done shakes or tiles on a whole house. I'm sure it's quite different.

At the PRAC class Certainteed Ok'd the method. Not a problem with it.

Always open to suggestions. That's what these forums are for. I just know this has worked for us a very long time.
 
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