Step flashing


#1

Anyone hem the top of their step and then hem the bottom of their counter to cleat to it? I seen this in a smacna article looked kinda good


#2

Hi,

No

Seems like the 2 different planes move seperate. This would cause them to unlock.


#3

yes I have . on some jobs it all has to be all copper so you lock the corners. On other jobs you just use a lead step flashing at the corners and mold it around to watertight the corner. lead molds nicely. Many roofer do not know this simple trick and there corners reley on caulk that will eventually leak.


#4

Yeah thought it would work good long as you hem your edges over an anvil and not tight on a brake it allows movement


#5

South Texas the humidity level is 50 to 100%., You’re going to get massive movement. With 6" counter run 1/2" from the roof deck and the 8X8 run behind it, a min of 3", it really doesn’t seem necessary. These two are designed to move differently. I can’t think of any reason to hem it other than cutting your finger? Hey, if it works for you, go for it.


#6

Nope. On corners, I have tinner’s wings that carry the water 2" or more past all corners. Won’t leak and doesn’t rely on caulk.

http://www.rooferscoffeeshop.com/images/photo_albums/30/710/Frt corner step1.JPG


#7

I think thats regional Tinner. a sheet metal worker or roofer could never get away with installing that detail in this area. flat locked corner or lead step.


#8

It’s actually international. And reccomended often. An ole-style flashing that works and has survived for centuries, from back before caulking was known. :smiley:


#9

Hi,

I do it like tinner.

That is not what pghroofer is talking about. He said the top of the step is hemmed and the bottom of the counterflashing is hemmed. He was not talking about the corner.

Can you show us a picture of what you were referring to?


#10

Smacna says its for wind uplift of the counter you guys use 3/4 locks I like 1/2 better but 3/4 seems to be the norm thing is 3/4 is ok for flatlock roofs but box gutters its hard to get the base of the iron on the high side and 1/2 doesn’t require as much heat to bleed all the way through the other side 3/4 locks take a lot more heat in pittsburgh all the older flat lock was 1/2 and they lasted 70yrs or so I think a 3/4 lock is springy but who knows doesn’t pound down like a 1/2 although heavier copper does better with 3/4 just a theory


#11

Well in addition to the SMACNA architechural sheet metal manual another resource that shows how we would do this is great book called “copper and common sense” by the CDA. Chimneys have to look uniform and neat without crazy wing looking corners, or God forbid caulking and tar. with the exeption of the reglets where we would use a urethene caulking like tremco dymonic color to match the mortor.


#12

Hi,

What are you talking about?

You go from hemming step flashing to soldering seams on box gutters in the same sentence.


#13

Sorry lefty I’m doing replys from blackberry and this was from email


#14

Rooferj isn’t copper and common sense by revere cda does publish a lot of documents though it might be cda and not sma that had the hemmed step I can’t goto copper.org from my phone


#15

2 words.
over
kill

gweedo.


#16

you need over kill with new england weather gweedo.
It is also what seperates different types of contractors.


#17

i read ya , but ive seen to many times over kill cause the leak rather than help prevent it.
and whats even worse is when you try to repair something that has bee over killed it makes the repair
more difficult or sometimes impossible.
call em like i see em.


#18

[quote=“gweedo”]i read ya , but ive seen to many times over kill cause the leak rather than help prevent it.
and whats even worse is when you try to repair something that has bee over killed it makes the repair
more difficult or sometimes impossible.
call em like i see em.[/quote]

You should come up north some winter to see what we are talking about. :smiley:


#19

Now, we’re talking about a copper or tin roof. Another animal all together. First, there won’t be need of any solder on front corners of chimneys or skylights. And the top corners get a soldered flat-lock that’s below the corner, not even with it.

http://www.roofing.com/images/topics/7435/img_1236627651.jpg


#20

Like qweedo said though, eliminating the corner, and the potential for a mistake could be overkill.