I guess it seeme like a trival question but I can’t remember for sure. probably because i wanted so much to forget ” Roofing ” . I Think the felt goes down first, as we used to do it. I also want to use Ice and water sheild. How far up do i go and what about the gable end? 1 course 2? thanks.
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Replies
I've seen the drip edge go on both ways - Over AND under. Don't know that it makes a whole lot of difference.
But I can't bring myself to put the drip edge on top. Anything that gets under there I want to have a good chance of running off.
Don't sleep with a drip. Call your plumber.
When I was roofing as a "Tadpole" 35 years ago my mentor gave me a bit of wisdom "think like water". If you were water where would you go? Put the drip edge down 1st, felt on top. Never give the water an even break or it will find a way in. Of course I've fallen on my head a few too many times and now work from a desk so I could be all wet.
It does make a little difference. As a rule I run it under at the bottom of the roof and over along the rake to the ridge. While a lot of roofers use an ice dam product called Grace over the eaves edges the metal mostly acts as a drip edge to protect the facia and not as a great flashing. Some even leave it out.
J.ust A G.uy W.ith A H.ammer
The guy who does most of my roofs goes under on the eaves and over on the slopes.
Another thing we've been doing is using the "D" profile drip edge. It's stronger, and supports the overhang of the shingle.
Look at the wrapper. Read the directions. Manufacturers want drip under at the eave and over at the rake. Our roofing practices also call for a strip of bull about 4" wide along all edges and flashing.
glad i dont roof any more.I bet its been 15 yrs since i heard that word( in that context)lol- bull- sucks trying to work around it.might just as well open the pail and stick your hand right in at the begining of the day cause you know thats what happens.we used to joke about someone could open a pail across the street and you'd be sure to get some on you
Yep.
Same thing happens with those simplex nails. Someone opens a box across town and one always appears stuck into the sole of your boot while you're running crown.<G>
The standard recommendation on ice and water shield is 12 inches up beyond the edge of the heated wall below. So, if your overhang is 24 inches or less, one course would be ok if the material you used were 36 inches wide, otherwise you'd need more. I've never seen it used on gables. Since ice dams don't form on gables, I would think it would be unnecessary there. You would want to use one strip wide under flashing in valleys, though.
A call to the manufacturer may bring a better answer.
Under at the eaves and over on the rake. For the Ice shield you need to find out the local requirements. Here, the requirement is five feet along the level. So a 12/12 roof would need to go seven feet up the slope inside the building line to meet code. That would mean at least three courses if your overhang was less than two feet.
First, you line the drip edge with a bead of pitch so it will seal on the roof deck. If there's no fascia you run a second bead of pitch inside the face of the drip edge to protect the end-grain of the plywood. Then you tack the drip edge to the roof with either nails or staples. Then you run a bead of pitch on top of the drip edge, and then you lay the felt on top of that.
If you're using Ice and Snow membrane, you skip the pitch on the top of the drip edge; the glue on the membrane takes care of sealing itself to the metal. Run the membrane just past the edge of the metal and then trim it flush with a knife. Use enough courses of membrane to go two to three feet above the lower end of the heated portion of the roof; a shallow pitch and lots of snow can back up water that far easily.
You don't need membrane on the rake run; you can even get away without drip edges there but it's schlocky to do so. Drip edges are cheap and make a nice visual detail in addition to their protecting qualities. You should run a course of reversed shingles up the rake vertically before starting the regular horizontal courses. This will lift the rake ends of the shingles just a bit and keep water from running off over the rake if the roof is a bit convex. It also reinforces the shingle overhang in the same way as the doubled first course does on the eaves.
Shingles should overhang the drip edge by ¾" all around. Felt or other underlayment should be trimmed flush with the nose of the metal edge.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
Dino, for what it is worth, the membrane goes directly to the roof sheathing, then install the drip and underlayment.
3/4" is a little much for over drip, 1/2" is more like it.
And pitch? Nuh uh, what, are you building a boat?
Yeah, I've been roofing nearly 20 years and I've never even SEEN any pitch on a roof. Must be a regional thing. I do use a lot of fancy caulks, though.
What we call pitch now isn't old-fashioned hot pitch; it's a thick version of bituminous roofing compound that comes in either pails or 300 ml cartridges that fit in a caulking gun. The only times I've seen roofing jobs with no pitch in the appropriate places are when I run into a real cheap-o job; usually that's when we find no tar paper/felt either and damn little detailing like double first course and so on.
The 'pitch' serves to seal out water from weeping underneath elements in the roofing assembly, either by gravity (ie, down slope) or by capillary action (upslope, sideways, along nail or staple shanks, any old which-way...). It can be applied to a wet surface and will stick and displace surface water very nicely. (Absorbed water in the roof deck has to dry out and evaporate over time through unprotected surfaces, usually into the attic from which the moisture must be evacuated by ventilation.) It is also a 'glue' or sorts; it serves to keep layers stuck to each other while the roof is being assembled. And in those situations where you simply CAN'T get a hammer, stapler, or palm nailer in under the overhang of an already-built house, it serves to glue down the last (dress) course of shingles.
I can't imagine doing a roofing job without using pitch at critical points, especially under drip edges. Especially with plywood as the roof deck and its highly absorptive endgrain. I want that endgrain sealed against water infiltration, even if the drip edge is physically ripped off by tree branches, ice slide, or whatever. Pitch on the inside of the metal drip edge will bond permanently to the edge of the ply, rendering it waterproof for many years to come; at least as long as a good grade of asphalt shingles.
And I honestly fail to see why you would put the membrane under the drip edge; that reverses the logic of shingling. Plus, why would you need another underlayment on top of a glue-down ice and snow membrane?
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
We won't ever be on the same page, I suppose I am just a hack. I've done my share of building thing right, and taking apart things where some nut went off the deep end.
As far as the membrane goes, read the f'n label. Get Andy to zen this one for you.
Oh ya, you head towards my house with a bucket of muck, and I'll toss your #### out.
Jeez, man. Is this your week to be bad? Lighten up. Nobody called you a hack but yourself. Sounds like you need Andy's zen more than me.
Be an edge. Not a drip.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
PS--The label on the membrane I use says to lay it on top of the drip edge. Just goes to show; the manufacturers can't agree either. So why the # should we?
Chill.
Edited 8/30/2003 1:57:24 AM ET by Dinosaur
Ha, why should this week be any different?
I've done the membrane both ways, 6 of one...1/2 dozen of another.
Mule,
If you've got a burning curiosity on the ins and outs of how and where to install waterproof shingle underlayment (WSU) (AKA Ice and Water Shield......), regular tar paper, drip edges and so forth, I'm doing demonstrations at the JLC Live construction trade shows in Columbus, OH the last week of September (26th and 27th) and again in Portland, OR the week after Thanksgiving. http://www.jlclive.com/index.asp
Believe it or not, there are specific industry (American Roofing Manufacturers Asso) and manufacturer instructions. I try to explain the logic behind each and then talk about the locations / connections that the ARMA and manufacturers ignore.
In a nutshell:
Tar paper goes OVER drip edge along the eaves edge.
Tar paper goes UNDER the drip edge along rake edges.
WSU sometimes goes OVER the drip edge along the eaves edge in the case of mineral surface products BUT Grace Ice and Water Shield goes UNDER the drip edge and down onto the facia board 1/2" - then the drip edge goes over.
WSU goes UNDER the drip edge along rake edges.
Mike Guertin