# reducing shingle exposure



## tomstruble

Gentlemen
Im looking at a small roof replacement.It a 12x17 approx 4 pitch it has 3 sky lite with maybe 5-6'' in between the units my question is would you cut the shingle exposure to 4'' on a roof like this?
The roof terminates at a stucco end wall with a dbble window about 6'' above the roof line,the end wall flashing is heavy ga aluminum .there is a vented soffit but no end wall venting would that shingle over vent work at the top end wall?The sky lite units are large about 3'x3' the homeowner wants to replace any manufacturer preference?


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## Grumpy

That's an old school method which pretty much died out with the popularity of ice shield. Infact when speaking with manuf reps they say it'll void their warranty. You're better off ice shielding the entire surface first before reducing an exposure. 

For a wal vent, you may try the Air Vent, Flash-Filter vent. I have used it before. 

I prefer velux skylights. Theyt will do custom sizes in some of their product lines.


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## tomstruble

thanks grumpy.p.s. your right i did go to the old school


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## tinner666

I use i and W, then reduce the exposure. I have a couple of trouble free Elks on 4" and 5" exposure.

The manufacturers know the shingles are worthless and want to RELY on the I&W, not the roof. 

This is a 3/12 the GC insisted I shingle on HIS house. Elks at 4". with I&W, and 'Dutch-Lapped' 4" tp 6". No butt joints. 9 years old. Up to 17" of snow. [url]http://rcs.si-sv2628.com/show_album_photo.asp?userid=30&AlbumID=288&file=1976&s=0[/url]

I love Elks at 5". The sealer strip lands on the flatest part of the shingle.


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## tinner666

I should have also mentioned this job. It's GAF or GP. I forget.
Fully Dutch-Lapped and the exposure went from full down to about 3-3/4" in keeping the lines straight. The Reps also came to the job several times and I'm sure they have their own pics stored somewhere.

[url]http://rcs.si-sv2628.com/show_album_photo.asp?userid=30&AlbumID=108&file=764&s=0[/url]

I have been certified by all of them at some time or another. Fancy toilet paper. They all know I think their product is crap now! :laughing:


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## tomstruble

so Frank you do reduce exposure with i&w ? and could you please explain dutchlaped shingles? thanks tom


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## Ed the Roofer

Overlapping the butt edges of the shingles by 3" to 6".

They used to make 3 tab shingles look like architectural shingles before any architecturals were ever made.

Franks measurements may vary. He's a wild man with asphalt shingles.

Ed


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## tinner666

No butt joints Tom. I did that to my own house.
I was going to make it rougher looking with 3" to 6" random tabs all over the place, but that got old in a hurry. So, I decided to save that for where I found joints in the 1x6's. When I found a joint in the nail line, I face nailed about 1" lower and slid tabs in, nailed about the nail line, with a tiny dab of caulk on the nail to act as a seal down. 

Finished the roof the day before the hurricane and it hadn't even sealed when the hurricane hit.


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## tinner666

Ed's right about the 3-tabs. Another thing was that I wanted a dimensional roof on my house. Elks and Timberlines butted look almost as flat as a 3-tab.

Some of my stuff was learned by................................................................................................. 'JackLegs'! 
Over the tears, I've seen many lapped edges and walls instead of cut shingles. Looks like crap to me. BUT, no leaks occurred!

The reps used to come to the shop and we'd sit around for a few hours discussing techniques, pros and cons. I've even done 'special order' jobs for some of those GAF, Certaineed, other reps.

Concenus was; Lapping was good at times, increased headlap, and never caused leaks.( I wouldn't thing of doing that on a 3-tab).
A lapped Elk has 8" of headlap!. 

Used a water hose on one, from the side, The water that squeezed through had an uninterupted trip down and out, without any sideways travel, since the lap created a 1/8" trough.

Ed knows me by now. I use I&W, but don't rely on it. Too many now RELY on it! Properly done, even a large storm won't make a roof leak if it's done over planks without underlay. Installation is the biggest cause of call-backs, not lack of I&W.


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## tomstruble

oh yes i get it thanks i like the roof, looks more wood shake like


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## tinner666

Yes it does. I get requests to do the same for others. Adds about 30% more labor. You wouldn't believe how much trouble it is keeping track of laps, nails, patterns, etc. 

I learned fast to leave both shingle ends un-niled until I had decided whether the adjoining shingle should go under or over! To keep the humps from growing, I tear off any 'double-lams' that are on the shingle I'm laying on top of.:blink: Gets kinda crazy!


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## tomstruble

i can also see how dutch laping away from the valley is a good idea do you always weave your valley?


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## Grumpy

I'm the kind of guy who does it like the manufacturer says to do it so if there is ever a failure of any kind, I have my butt covered. I wouldn't dutch lap or reduce exposures without written permission from the manufacturer.


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## tinner666

Not always Tom. It requires laying out the shingles all over the area to soften first. Even to Cal-cut one, 1/2 of them need to be laid out to soften.

Manufacturer did sign off grumpy. They always do. Not that it matters,IMHO. They're going to duck any responsibility if they can. I've been around that tree too.
FWIW, no tech that writes that crap has ever been on a roof and hasn't a real clue.


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## tinner666

PS- 5" exposure on Elks makes the water drip off from one to the other, along with the better seal down properties, instead of wicking so bad. 
Butt joint allow a LOT of water between the shingles. Sometimes, they get overwhelmed and leak there. I fixed many of them too.


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## Grumpy

tinner666 said:


> They're going to duck any responsibility if they can. I've been around that tree too.
> FWIW, no tech that writes that crap has ever been on a roof and hasn't a real clue.


 Agreed and agreed, but when I sit in a court of law and say "Your honor I installed it exactly as the manufactyrer stated in good faith that they know how to install their product." The point is I want limited liability should there be a failure of any kind. If youa re getting the manufacturer to literally "sign" off that's great. If you are getting a verbal "Um yeah that should be ok", I pray for you.


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## tomstruble

this is the roof that im looking at sno on the roof but you get the idea.She wants to change out the sky lites and re do the roof,i was hoping to get some venting at the wall but that hard coat stucco scares me and the left side of that window dont look to good any advice?


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## tinner666

If possible, I'd make single a U shaped, (With squared bends, of course), piece of flashing to fit between the 2 skylites. Make the top wider than the bottom for a loose fit at bottom, (1/2" total play is OK, it won't bind in hot weather.) I also believe, I'd make a pan that extends all the way from one end of thoase skylights to the other. Any joint in the center will be headed for trouble! A single pan could also be 'notched' and folded to allow water down the middle without harming the integrity of the back pan. With or without the notch, that's the weak point. On reflection, I'd turn up 8"-12", and at the center, use the'extra' metal to literally close/cap the weak spot off. That would be first choice. There would be a small 3tablespoon bed of caulk at the 2 outside corners and one crossing the open to set the pan into.

More in a moment.


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## tinner666

For stucco specifics, go here http://www.your-leaking-house.com/sites/your-leaking-house.com/forum/index.php and ask Carl Brown.

Me, I'd bust the stucco out at least up to the bottom of the window and install a pan or other flashing so the water can exit the wall. Then, I'd get some wall-vent and install it. (I saw at least 1 dutch lap on that roof!:laughing: )


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## tinner666

Grumpy said:


> Agreed and agreed, but when I sit in a court of law and say "Your honor I installed it exactly as the manufactyrer stated in good faith that they know how to install their product." The point is I want limited liability should there be a failure of any kind. If youa re getting the manufacturer to literally "sign" off that's great. If you are getting a verbal "Um yeah that should be ok", I pray for you.


Agreed again grumpy. But the metal book says to cut the panels off and add Z-bar. Screw that. I bow fold and then add a Z-bar, or sometimes a locking strip attached across the ridges and a ridge locked to it.

Their stated reason? Nobody will take the time to do it right. That's why my bids seem to have no relation to other bids on many jobs. :laughing:

Same for the shingle suppliers. Like I said we used to hang together and hash ideas, causes and effects for hours. 

Did you know they claim that bending a shingle to nail under it will crack most of the fibers? If it isn't lifted with an almost straight lift, as opposed to a 'decent' bend, that one just got ruined. 

Anybody seeing this thread and not in the know, grump and I aren't arguing, we're discussing and debating this.


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## tinner666

BTW TomS. Any damage on that side wall? Lot of staining by that gutter.


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## Ed the Roofer

tinner666 said:


> BTW TomS. Any damage on that side wall? Lot of staining by that gutter.


Frank, you should know the obvious answer that saves all roofs from what you must have read at Nachi so far.

But, in this case, they would be extremely correct.

That leak stained stucco wall does in fact need a kick-out flashing to be installed on the upper roof, bottom course.


Further, I agree completely about bending the top of the Standing Seam panel AND using the Z-Flashing, or actually an oversized on one part J-Flashing.


For that double stacked skylight, I would try to find ONE oversized unit to avoid the center flashing details all together.

You can use Smart Vent from DCI Products as an Exhaust Vent on the top course of shingles and then shingle over the top of it and then install the apron flashing from the Roof-To-Wall transition.

To cleanly cut away the stucco, use a 4" grinder with a diamond blade and follow a straight edge line for cosmetics. See if there is ANY room at all to sneak the vertical portion of the Roof-To-Wall Apron flashing behind there, even if it only goes 1-2 inches, without cracking it.

Otherwise, it's time for foam backer rod and a compression seal for a tight surface mounted flashing.

Ed

But, I add one step to that procedure. Where I bend the top of the panel back, so it faces the eave, I also leave the sides on and before I bend them in for a tight fit at the bent panel part, I insert a dab of NP-1 into the open corner joint. Then I peen the sides tightly to the bent panel.


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## tinner666

I was sure of that Ed. I was wondering if he had noticed any on the inside. I'm not much of a wordsmith, am I? Good thing I roof better than I talk or type, eh?


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## tinner666

"But, I add one step to that procedure. Where I bend the top of the panel back, so it faces the eave, I also leave the sides on and before I bend them in for a tight fit at the bent panel part, I insert a dab of NP-1 into the open corner joint. Then I peen the sides tightly to the bent panel." Yeah, I forgot to add that. Thanks Ed.


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## tinner666

Some things are soooo second nature, I easily forget to mention it. Kinda like trying to explain how the legs work when I walk naturally. I don't know what's going on, but I put 1 foot in front of the other until I get there!


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## Grumpy

Yeah I talked with someone once and when I saw two valley accessories and asked, why did you change it it seemed like it'd work better the first method, they said someone similiar to the fact that nobody took the time to do it right. IN other words they lowered their standards but in doing so they made it "fool proof". It was so eazy you couldn't mess it up but if you took the time, you could have done better.

What a phucked up world we live in.


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## tomstruble

wow you guys are great thank you.I like the u shaped pan idea and a full lenght head flashing is the way to go i got alittle lost on what to do with the head flashing inbetween the units tho.Maybey i can just put a 1inch slot in the vertical leg of the 1 pc head flashing inbetween the units to let it drain without having to wrap it around the heads?

Im starting to think iim going to have to cut the stucco at least to the sill i think its leaking thru the window the more i look at it.
This is really the first time i got a good look at the roof and yea i see where it needs a kickout

Ed do you use that oversized j detail on your ridge or just on your end wall?

i always do a kick out that and head drip most imortant flashing for a sider


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## Ed the Roofer

tomstruble said:


> wow you guys are great thank you.I like the u shaped pan idea and a full lenght head flashing is the way to go i got alittle lost on what to do with the head flashing inbetween the units tho.Maybey i can just put a 1inch slot in the vertical leg of the 1 pc head flashing inbetween the units to let it drain without having to wrap it around the heads?
> 
> Im starting to think iim going to have to cut the stucco at least to the sill i think its leaking thru the window the more i look at it.
> This is really the first time i got a good look at the roof and yea i see where it needs a kickout
> 
> *Ed do you use that oversized j detail on your ridge or just on your end wall?*
> 
> I always do a kick out that and head drip most imortant flashing for a sider


Most of the relatively few standing seam roofs that I have done, usually dead ended into some version of a wall at the top of the panel, with dormers and hips being the only minor differences.

I also bend them the same way on those too, but obviously on an angle to coincide wuith the hip. Valleys are different. I prefer an oversized apron flashing under the panel, rather than the supposedly called for cleat to secure the bottom of the panel. Al that dang thing does, is raise the height of the center of the panel.

Ed


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## Ed the Roofer

This topic really tok a detour from reducing shingle exposure.

Good metal talk though. It's rare I ever have to do actual metal roofs, but at least I know how, the Right Way. Or, at least my preferred Right Way.

Ed


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## tomstruble

ive done a few over the years, i love bendin metal for some reason and its great to have guys like you and Frank and Grumpy to talk about it with
thanks again


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## tinner666

"Maybey i can just put a 1inch slot in the vertical leg of the 1 pc head flashing inbetween the units to let it drain without having to wrap it around the heads?"
You could, BUT, you will be creating a 'potential' weak link in the system.

My technique? I take 1-3 pieces of 12" metal and mock up 1-10 senarios before making a final decision. And a 6' piece never quite fits like that 12" mock-up! 
I can't go back from this answer box, but I think thye were 2' skylights. That's only about 60" of back pan, with less than 4' of roof above it. Shouldn't be a problem.


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## tinner666

tomstruble said:


> this is the roof that im looking at sno on the roof but you get the idea.She wants to change out the sky lites and re do the roof,i was hoping to get some venting at the wall but that hard coat stucco scares me and the left side of that window dont look to good any advice?


After going back, I'm more confused. Are they 4' across? One view looks like 2'ers. other looks like 3-4'ers???
Only 38" to the wall. I'd still go full lenght. 
Reason? They're not like a chimney between them where water can run around a back-pan. You join 2 pans there, no caulk in the world will work long-term, even with hemmed ends. 
This is one of the very few that I might end consider a 1"-1-1/2" tall water diverter above the pan, about 6" longer on each end, come to think of it. You would sleep at night knowing that no amount of rain would ever back up enough to 'over-run' the top of the back-pan, which looks like it could be 4" tall for 6-8'.

Overkill, but bullet-proof.


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## tomstruble

they are 42'' wide and i see what your saying ,do you think i should make the diverter 2 pc pulling it up in the center to get some pitch to the outside of the skylites?


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## tomstruble

because of the roof pitch velux wants a raised curb


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## tinner666

I know they want a raised curb. I' haven't seen any problems with 3/12 roofs yet.

I would pitch a diverter about an 1" or 1-1/2" each way. It's only a 3' run, but that is a lot of snow above them. Put the diverter 8" to 1' higher and a monsoon won't casue it to leak.


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## tomstruble

thank you Frank


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## Jasonthompson

u shingled that 2/12 section of roof??? are u crazy shingles are not made for that low of pitch. I would of used a peal and stick or single-ply system. Things that are made for low slope.


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## kimboy

I was sure of that Ed. I was wondering if he had noticed any on the inside. I'm not much of a wordsmith, am I? Good thing I roof better than I talk or type, eh?


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