Your information is incorrect. This coming from someone who worked in the
ice dam capital of the USA.
The granules on shingles is for water diversion/dispersing, otherwise water
would _shoot_ down fast like on a metal roof.
If one makes the shingles tight against step flashing, water is dispersed
and can go under the shingle, taking the path of least resistance. You
should have a small channel at the shingle and any accessory, such as step
flashing, pot vents, soil boots, etc. You _want_ a channel for a path of
"Lots" of roofing cement should _not_ be in any roofers vocabulary. A small
bead on the _hidden_ edge is all, which is needed. "Liberally coated" is a
term used in hot mopping, not shingles.
With your attitude of how you want your roof done, you will never get a
slowing down the water as you state is their SECONDARY purpose. at
best. The primary purpose is to protect the "fabric" of the shingle
from sun and weather damage. When the granules dissapear, the felt
backing of the shingle is soon gone as well. Another MAJOR purpose of
the ceramic granules is to provide fire resistance. If you do not
believe me, see: http://www.nrca.net/consumer/types/asphalt.aspx
I also know what step flashing is, and how it is installed here.
Step flashing is fully coated on the bottom side with roofing cement
and nailed down at the top edge, then the shingle is placed over the
flashing and sealed down with roofing cement. The shingles are cut to
leave roughly 1/2 inch gap between the end of the shingle and the step
flashing. The next step is then placed over the shingle, with the
metal tab extending JUST ABOVEwhere the bottom end of the next shingle
tab will end. (Up to 1/2 inch of step flashing MAY show below each
shingle tab, but I prefer to see NO flashing showing beyond the
It is done this way here to prevent the shingles from lifting off the
step flashing in high winds and to seal the flashing to the roof. It
is generally only nailed to the roof deck, making it possible to
remove and replace step flashing when replacing a roof without
disturbing the aluminum or vinyl siding most commonly used on the
upper floor walls and gable ends of houses here.
The roofer who installed the first replacement roof on our house
(before I bought it) did not seal the step flashing and we had a leak
down the wall that dripped out of the door between the house and
garage when it rained within a year of us buying the house.
We replaced that roof - my father who worked for many years in
construction, along with several experienced friends and myself. When
Dad saw how the step flashing had been installed (it was exposed to a
large degree ) he said the guy who installed it should be shot.
The new step flashing was installed with fibrated plastic roofing
cement on both sides - and it never leaked again. Used just over a
quart of cement between the step flashing above the garage and the
When the shingles (first generation fiber-glass -( not the best
quality stuff although it was "high end" at the time) started to crack
and curl after loosing much of the granule coating, I paid a roofer
(who did the roofing on many of the houses my Dad worked on over the
years) to do the job with laminated architectural shingles and
specified I wanted tar paper on the whole roof, and the step flashing
cemented. He said most people don't do it that way any more because it
costs more. "how much more?" I asked him. He said MABEE $200. I said
$200? DO IT!!!" He said he wished everyone thought that way -
See http://www.renovation-headquarters.com/roof-flashing-wall.htm for
confirmation that I am not the only one who thinks this is the right
way to do it. And no, I didn't write it.
shows the same method but does not mention the roofing cement.
Also see http://www.youtube.com/watch?v=rzOn_8t4mZ4
As for the "root flashing" or "L" flashing, it is not uncommon to nail
it down where required and cover the flashing with a top row of
shingles cut to fit (exposed part only) stuck to the top of the
flashing with roofing cement. Makes the "L" flashing totally disapear.
Again, not as common as it used to be because it adds a small amount
to the cost of the job.
If the job's worth doing, it's worth doing right.
On Nov 11, 11:49 pm, firstname.lastname@example.org wrote:
Man, I do not understand that stuff at all. How are you supposed to
rip a roof and reuse the flashing if it's glued top and bottom with
I also don't understand about you "specifying" to a roofer that you
want building felt on the whole roof. Every single roofing
manufacturer in existence already specified it in every piece of
literature they have, and on the every freaking bundle of shingles.
It would be like telling a car dealer, "Hey, make sure there are tires
on those wheels!"
Omitting the building felt or other underlayment automatically voids
the warranty. The fire resistance rating of the shingle is determined
with the building felt in place. It would kind of suck if your house
burned down and the insurance company refused to pay because you had
an un-rated roof assembly.
As far as the ice damming, that is not as much of a function of
shingling or flashing technique as a lack of insulation low down on
the roof, and that's where most ice damming occurs. That is one
reason that code requires self-sealing membrane at the eaves extending
up the roof a couple feet past the wall line, but does not require
membrane at the side wall. If you have a history of ice damming at
your side walls, due to insufficient wall insulation, then self-
sealing membrane should be installed extending up the wall and on to
the roof, and then the step flashing should be installed as the
shingles go on. The step flashing gets nailed only to the wall to
You do some things in some very different ways. I don't see any easy
way to do a total ripoff and reroof after you've - sorry - ruined the
step flashing with the roof cement. How do you strip a roof and reuse
the step flashing? That first link kind of contradicts itself and is
vague on the point of reroofing. Here's what it advises about reasons
for reroofing: "Flashing needs replacement. (It is worth noting that
most roofing contractors will not replace existing flashing when re-
roofing. The reason being that most flashing sits on the roof deck,
below the existing shingles.)" That is not true at all about step
flashing, so I'm not sure what they mean about most roofing sitting on
the roof deck.
Your second link shows exactly what I described above, except they
call the self-sealing membrane underlayment (which could be plain old
15" building felt). No mention of roof cement, all nails in step
flashing are into the side wall only. That link specifically
disagrees with what you have said you do.
Okay...that last video just pissed me off. I am, seriously, going to
call GAF tomorrow and rip them a new one. The video has at least four
major mistakes. "I ALWAYS replace ALL flashing. It's not worth
reusing it to save a few bucks!" Are they kidding me?! Try hundreds
and hundreds of dollars. I'm supposed to pull siding, and chase out
grout lines to remove flashing? Then install new flashing, reinstall
(or, more likely, replace) the siding, regrout, and REPAINT? For a
reroof?! Those guys are on crack.
They show the chimney with nice copper flashing, and the voice over is
telling you to remove all the flashing. There's no reason to replace
that flashing. If you nail into the roof, yeah, sure, it'll be easy
to remove that flashing - ruin it - but easy to remove it. That makes
a re-roof more expensive. Then what are you supposed to do - slide
step flashing up under the siding somehow? Yeah, easier said than
done, and most times essentially impossible. The step flashing should
extend up the wall a good three or four inches minimum. It was also
really light gauge aluminum. He's talking about replacing all of the
flashing as it's not worth saving the "few dollars", then he installs
On Thu, 12 Nov 2009 00:10:14 -0800 (PST), RicodJour
You don't re-use flashing - generally speaking.
The VAST MAJORITY of shingled roofs in the last 10 years have not got
tar paper or roof felt on them
hits, and the eve is in shade, or the area next to the wall where the
step flashin is is in the shade, you get ice buildup - also known as
ice damming, even if the insulation is excellent. It happens sometimes
on our house which has over 18 inches of blown fiberblass in the
attic. - but on the roof of the unheated garage which butts up against
the south-east wall of the house.
As I said - the step flashing is not necessarily re-used
And the first link says into the roof deck only - which is how it is
usually done here - allowing the flashing to be pulled from behind the
siding and easily replaced.
That is only necessary if you do things bass ackwards and nail the
step flashing to the wall instead of the roof.
On Nov 12, 10:55 pm, email@example.com wrote:
Well, if the last guy makes sure you can't, I guess that makes your
method required. I try really hard not to screw the guy that comes
after me. I install access panels, leave some slack in the wiring so
there's some play at the box, don't bury junction boxes, make
maintenance as easy as possible, etc.
It takes no more time to install the flashing to the wall in new
construction, and it doesn't change anything other than allowing the
flashing to be re-used. Where exactly is the harm in that? I'll get
to the part where the major players recommend how I do it a bit
You're married to "this is the way we've always done it!" and refusing
to see that you wouldn't be giving anything up.
That's just simply bullshit. There are hacks everywhere, but the VAST
MAJORITY of contractors are not hacks. Most people read the
instructions and follow the manufacturer's installation
recommendations. You do know that code requires you to follow the
manufacturer's instructions on roofing materials, right? You do know
that the IRC requires underlayment, right? What the hell are you
arguing about? Take away a little education from this instead of
arguing while standing on no legs.
Here's the NY version of the IRC, which has very minor differences.
No differences in the underlayment requirement.
§RR905.2.7 Underlayment application. For roof slopes from two units
vertical in 12 units horizontal (17-percent slope), up to four units
vertical in 12 units horizontal (33-percent slope), underlayment
two layers applied in the following manner. Apply a 19-inch (483
strip of underlayment felt parallel with and starting at the eaves,
fastened sufficiently to hold in place. Starting at the eave, apply
inch-wide (914 mm) sheets of underlayment, overlapping successive
19 inches (483 mm), and fastened sufficiently to hold in place. For
slopes of four units vertical in 12 units horizontal (33-percent
or greater, underlayment shall be one layer applied in the following
manner. Underlayment shall be applied shingle fashion, parallel to
starting from the eave and lapped 2 inches (51 mm), fastened
to hold in place. End laps shall be offset by 6 feet (1829 mm).
Go read your code, come back and tell me what it says.
Oh, really? You're saying that the UL and/or NFPA unilaterally
changes the manufacturer's roofing system and omits the underlayment
requirement from the installation? Go visit the NFPA site and read
any of their numerous PDFs on asphalt and fiberglass roof shingles -
they all say that they are to be tested as per the manufacturer's
installation instructions, which includes the underlayment.
And I don't have to flush the toilet, but I do. It's a courtesy for
the guy that comes after me, a cost savings for the owner I'm working
for, and a sign of respect for the house I am working on.
Okay, you're shooting the messenger. Fine. You've picked up a copy
of Fine Homebuilding once or twice? Here's a snippet from their web
site from their article on how to install step flashing:
"Most of the time, I like to avoid putting any extra holes in the roof
surface, so I nail step flashing to the sidewall only, where both the
next piece of flashing and the siding will cover the nail head."
The Journal of Light Construction, ever heard of it?
Q. What is the best way to detail the connection of a pitched roof
abutting a sidewall?
A. According to the National Roofing Contractors Association, when the
rake edge of a pitched roof intersects a vertical wall, #15 felt
should be laid under the shingles, extending 3 to 4 inches up the
vertical wall. Metal step flashing (flashing shingles) should be used,
with one flashing shingle for each row of shingles. The flashing
shingle should be bent to extend under the asphalt shingles on the
roof about 2 inches, and 4 inches up the vertical wall. Each metal
shingle should be placed slightly up-roof from the bottom edge of the
asphalt shingle which overlaps it. Nail the flashing shingle with one
nail along the upper end of the vertical leg, as shown in the
That article referenced the National Roofing Contractors Association
recommendations, you can look that one up on your own as you already
included a link to a page on their site.
Generally there's about an inch gap above the shingles to the bottom
of the siding. How can you force aluminum flashing (which BTW, I
don't use) three or four inches up under the siding? What about the
nails holding the siding/trim in place? What about stucco siding?
No, it really isn't. I thought you were someone who appreciated good
work, and were on this newsgroup to help other people. You're arguing
that code doesn't matter, the testing agencies are to be ignored, that
the manufacturers don't know what they are talking about, that there's
no problem with voiding a warranty and there's no point in making the
next guy's job easier/cheaper.
PLEASE. Do yourself a favor and go check what I've said. It doesn't
matter what is done in a particular neck of the woods if it violates
all of the things I mentioned above. There's a right way and a wrong
way, and you seem to be pushing to legitimize the latter.
There's nothing wrong with learning. There is something wrong with
being afraid to look because you're afraid you won't like what you
learn. By all rights you should be paying me for the education I'm
giving you, instead of arguing about it.
Forget about where I live and how I do things. Go check your local
code and let everybody know what it requires.
On Thu, 12 Nov 2009 21:30:09 -0800 (PST), RicodJour
3 out of 5 roofers I contacted brfore having my roof installed this
last time would not install "roofing felt" over the whole roof.
Only 2 would, and neither one did it as standard procedure.
That may be what is recommended - not necessarily what is actually
I'm saying the insurance company will not fail to pay because there is
no roofing felt.
Makes it a royal bitch to replace flashing that DOES require replacing
when it is nailed to the wall under the siding. And you don't have
much to nail it to either with glass-clad or ten-test sheathing.
be OVER the shingles.
THAT IS WRONG. You won't argue that, I hope.
I said if any roofer put my roof on with the step flashing showing,
he'd be tearing it off and doing it over..
Someone said I was wrong there.
You won't argue that either, will you?
And I have installed quite a few roofs over the years - including step
flashing (even into brick walls) and even cedar and white pine shakes.
Even a few of the old interlocking square shingles.(repair only - now
THOSE are fun).
Just not young enough to do it any more so I hired it done this time.
ANd I had to be specific to get it done the way I figured was right -
which meant 15lb felt (tar paper) over the entire roof.
You are not arguing I am wrong to demand that, are you?
I'm NOT SAYING it is not "required" - just saying it VERY OFTEN is not
That is from my experience - can't argue with that either. What is, is
- not necessarily what should be.
Also not saying you cannot nail step flashing to the wall -
The important thing is it only gets nailed to one or the other - and
the guys I learned from nailed to the roof and sealed the step
flashing to the roof, and stuck the shingles to the step flashing with
fibrated plastic roofing cement (usually Bull-dog wet-stick) and those
step flashings never leaked, and the high winds we often see here
never tore the shingles away from the flashed part of the roof. When
you get huge drifts of snow banked against the wall, then get 2 days
of thaw and a hard freeze, you get ice in the valleys and against the
walls (where the step flashing is) and often on the eaves too - no
matter how well insulated the house is. Insulation makes a BIG
difference in normal conditions, for sure.
The way the step flashing was installed on the original roof when I
bought my house it DID leak when the snow piled up against the wall,
melted and froze. It was not sealed with roofing cement, and not
nailed to the roof. It needed to be replaced, and the siding was on
the wall. Not fun removing the screwed up flashing - I can tell you
Cann\\'t really argue THAT either, can you??
How, pray tell me, do you nail step flashing to the wall when doing a
re-roof on a house with aluminum siding????
I'll tell you - you DON'T. You nail it to the roof.
Knit or woven valleys are common here too for the same reason - they
don't blow off and they don't leak. They are generally done over a
steel or aluminum valley flashing sealed to the roof with roofing
cement and covered with self stick or torch-down roof membrane so they
don't flex and crack. The old-timers and quality consious guys do it
this way - the guys doing "tract houses" or houses built on spec do
it the cheap and easy way - metal valley flashing and shingles cut to
leave the metal valley exposed.
You just like to argue. You keep saying I'm wrong. Mabee in a perfect
world I would be.
Since you like GAF for reference, you better read up on underlayment.
Especially the part about in order to maintain UL Class A fire rating. You
did not contact any professionals for an estimate.
Not being done, does in noway make it the right thing to do. Geesh!
You know this how?
I suppose you're referring to me. Read this slowly, NOWHERE did I say step
flashing is supposed to go over the shingles. I said APRON flashing. APRON
is different than step, need I explain the difference?
My reference was step flashing will be seen, by having a channel or where
siding does not run tight to roof line. I say you're wrong to cover as much
as possible (make it tight as possible). A half inch channel will allow
water to flow. If you ever been involved in fixing a mess where the
material was tight against the upside leg of step, you would see debis
under that shingle. This is caused by restricting or obstructing the flow
Oh my gosh, we have a winner. You are showing how much you _DON"T_ know.
Step flashing is _never_ "into" brick! Besides being vitually impossible to
do, that is why you brake & install counter flashing. The step flashing is
on the outside of the brick. Next time you attempt to B.S. someone, you'll
at least have your story straight.
For someone who talks about ice dams, all you talk about is felt as
underlayment. There is a product out, or has been out for 30 years or so,
called ice guard. Every major player in the manufacturing of roof
materials, offers it. Maybe read up on it, so you can say you've installed
thousands of feet. If you wanted the job done right, you should at least
know about it.
You know, you may BS people, which don't have an inkling about this
profession. However, you keep digging yourself deeper & deeper attempting
to show you know something. When in fact, you really don't have a clue.
Unfortunately, too many people think like you do. The "oh well, this is the
way we do it". If they got into the real world, and had to do quality work,
they probably would be washing dishes.
Good grief. That doesn't mean you have to butcher it for the next person. I
live in tornado alley, we are beyond the high winds. And, never have seen
shingles torn from step flashing. Entire roofs gone, second stories gone,
not just shingles by the flashing. I do know, if we ran into a job where
someone cemented all the flashing down, and it couldn't be saved/salvaged.
The charges for _hidden/extra_ work incurred would run into hundreds of
You need to read up on causes of ice dams. Ice will form on eaves first
(not sometimes as you say). I'm not going to explain it to you. You really
need to read, and not on some vacuum cleaner site.
Wow, any valley done correctly, will not leak. Metal, woven, or a half
woven w/cut back. You absolutely contradicted yourself. A metal exposed
valley is more time consuming than having a closed valley. If you really
knew anything, you wouldn't have made that statement. Torch down would get
you a fine around here, besides being outdated at least 30 years. You don't
seal the back of metal valleys, where are you getting this information? You
don't run metal under a closed valley, it would serve zero purpose. You
certainly are misinformed.
No, it's not arguing. He just doesn't like misinformation spread.
By "professionals" I mean they do it for pay, for a living. It's their
"day job" and they are in the yellow pages under "roofers"
I never said irt WAS right - or I wouldn't have demanded the
underlayment be installed. Would I??
is the assistant operations manager? Good enough for ya?
IF it was you, I clearly stated STEP flashing and you said if I wanted
it done that way I'd never get a "professional" to do it for me - yada
yada yada.. If it WASN't you, whoever it was DID say that.
On some 100 year old brick farm houses the step flashing IS set into
the brick - no counter flashing used. - and NOT nailed to the roof in
that case. Martared into the brick joints and some real nasty angles.
- Self sticking orTorch down roof membrane as it is also known
SMART ASS - I never said it was right or acceptable - I said that is
how it is done. Get over it, and yourself. Fer cryin' out loud
Exactly, it doesn't make them a professional. The first clue would be
having to "ask" for underlayment.
And, being in snow country, where's the ice guard? You got what you
Now, if you were to say she was an adjuster, you would have something. But,
working in an insurance office, doesn't remotely qualify someone to be an
adjuster. You should know an adjuster requires qualifications not obtained
in the office. You keep trying to pull yourself off as someone with
knowledge, and end up looking like a, well, like a fool.
Nope, look again! I commented on the entire cloud 9, you attempted to be
on. Go ahead, look!
It's called a one piece. See, you don't even know all counter flashing
_should_ be tucked into mortar joints. Nasty angles? Who are you trying to
kid? That's the work I loved to do, and I can tell, you've never done it.
You cut joints if there isn't any, with a angle grinder. There's some more
information for you, for the next person you try to BS.
LOL... Don't be upset because you got called out on your lies, and caught.
What's that saying, it's better to be thought a fool, than to open your
mouth and remove all doubt. You probably want to take that saying to heart.
BTW, the technical term for the cut in mortar joints is called a reglet.
And, in the old days those one piece were laid while the chimney was being
built. Just a bit of information, next time you feel like telling stories.
My point was about placing an obstruction in the path of water flow. I
don't want to get off topic taking it how a shingle is constructed. Heck,
we could go into opacity of the granules as well, but it has absolutely
nothing to do with water flow.
No, but you created a problem when you go to replace that roof. If you
_must_ use some existing flashing, you'll have a heck of a time trying to
get it unstuck. More is not better. Your analogy would be similar if
someone were to say, just spread tar all over everything. It never leaked.
There's a correct way to flash, and the way your father did it. Sorry, but
professionals would never do it the way your father did.
Wow, what a nightmare, especially if one would to have stucco siding, as
the link you provided.
Yep, you live in an area without strict codes. I have never worked an area
where felt was an option. No doubt why you get away with certain methods.
The problem with the first site you provided is, they appear to be
"experts" from vacuums to software & everything else. I really hope you
don't think this site would convince me or anyone else besides yourself, to
take them seriously.
The problem with the second site you provided is, someone cut the step
flashing too short, and forgot about the starter strip. I don't believe in
regulating the internet, but stuff like this shouldn't be allowed.
The problem we see with GAF, is they don't even recommend using a second
layer of protection at step flashing. Such as a small bead of sealant along
the hidden edge, let alone _embedding_ step flashing in cement. Of course,
they are using a 10"x7" step flashing, instead of standard size. As I said
_B/4_, around here condominium associations _require_ all apron flashing to
be covered by roofing material. Put some thought into this one, there is
no doubt water will be trapped. By shingling over the flashing, you depend
on the sealant to be you first & _only_ protection from intrusion. Water
will sit trapped, until it evaporates or takes the course of least
It's your roof, there's plenty of people to take your money. Unfortunately,
you will find them.
On Nov 11, 8:08 pm, firstname.lastname@example.org wrote:
I have never heard of "root flashing" for anything roof related. I
did a quick Google and that word, I do not think it is what you think
it is. Check it and see. The only places that "root flashing" showed
up in a search is where the OCR misinterpreted 'roof flashing'.
The flashing you are referring to is called, on both sides of the
pond, apron flashing. A chimney has apron flashing bridging the gap
from the roof to the chimney at the bottom edge of the chimney, step
flashing running up along the sides, and a counter flashing which is
tucked into the mortar joints and wraps down to cover the top of the
apron and step flashing.
There is some rather heated discussion between the two camps on how
step flashing is covered by roof shingles. Some say to run the
shingles tight to the wall, and others swear there has to be a gap.
If the flashing is installed correctly and of sufficient size, either
will work and not present problems.
There is never a situation on new construction where a nail has to be
placed through the flashing and the nail head left exposed. Cleats or
clips are the standard way to deal with the problem. If a roofer
doesn't know how to install a cleat, he isn't a roofer, no matter what
he does to earn money.
On Wed, 11 Nov 2009 19:26:28 -0800 (PST), RicodJour
And sometimes at the high side of the chimney too - chimneys are not
always at the peak of the roof
The guys around here call it "L" flashing or root flashing., but yes,
it is also called apron flashing. Most often tucked up under and
behind the bottom row of siding on the upper floor walls. (Most 2
stories in our area are brick veneer on the bottom floor with aluminum
(or lately vinyl) siding on the upper floor.
Excellent analysis, Kerry. The age thing may have crept up on you -
mine seems to be running! ;) - but you've lost nothing. I'll
reinforce your words in my reply to the OP.
BTW, post more often. We need experience and sharp minds.
Okay, we got a picture, now all we have to do is get a picture that
actually shows in detail the area in question. You are wasting your
and other people's time by being parsimonious with the required
information. We don't need a picture of your very nice house - we
need a detailed, up close and personal picture of the problem area on
your very nice house. That single nail might be the problem, or you
might have a bigger problem. Without better information from you, you
might be getting a useful response or not - you'll never know, and we
Use the zoom on your camera, stick the camera out the window and take
I am a professsional roofer located in CT. The leak is probably at
the pitch change between the upper steeply pitched roof and the lower
"moderately" pitched roof. The step flashing in this area is two
small to handle the backwash of the pitch change. We usually cover
the entire lower pitched are with self adhesive ice & water barrier
and install an oversized flashing detail at the pitch change the
covers the last two sourse of the low pitched roof. Good luck!
I don't know about that. It's possible, but the OP's sorry picture
has the arrow pointing to a spot that's a distance away from the step
flashing on the pitched part of the roof running along that wall, and
under the window. There's no up-slope area, just the wall and
window. We need better pictures! Coloradotrout, provide them
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