Would you install the drip edge under or on top of the bitathane or ice and water? What about facia drip edge and rake drip edge?
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Replies
yes
I run the bituthene directly on the plywood, then the metal drip, then a 6" strip of bit or vycor, or start from the metal again with underlayment to the ridge
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With tar paper the drip edge goes under on the bottom edge, over on a gable end.
DanH
On my jobs that is wrong.
On my rakes the tarpaper is always under the metal edge.
When water inflitrates under the shingles on that edge then it hits tarpaper and not plywood.
Rich
Absolutely!
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It is something that I have been curious about for a while as well. When I worked for a GC we did it drip edge over ice and water shield. But he did a lot of stuff wrong and now I am on my own I have to protect myself. I have found that a lot of folks in this industry try to re-invent the wheel and ignore the wisdom in old techniques. I have seen many roofs with felt over drip edge and thought that it made a lot of sense. That said, the drip edge over ice and water shield technique sounds good but what is so bad about drip edge under ice and water shield?
"what is so bad about drip edge under ice and water shield?"I don't think I said it was bad, my way is just beter - more practical too.See, when we put the plywood sheathing on, we want to get it dried in immediately. Much of the time, the fascia is not done yet, so it is impossible to put any eave edge in place before the dry-in.So we start with the I&W, then finish to the ridge with tarpaper or nowdays, Rooftopgaurd II.Then after the trim is on and the plumbers have made their penetrations and it is time to start roofing, we run the metal, strip in in and start shingling.Sometimes we want the RTG II over top of the I&W shield all the way from bottom up, so we leave that bottom 6" un-nailed and can slide the metal in under it.Most of the rotted fascia I have repaired in tear-offs over the years was from water that wicked up over the top of the eave edge behind shingles and then ran under it back down to the fascia. The rest was where not enough attention was paid to being sure to leave a drip free so water would bleed back from th e drip edge and run down over the fascia. That was especially bad where gutters were hung tight and those hanger penetrations led water in
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When you put your sheathing on before the facia, how are you cutting the tails back? Or are they already done? Assuming you don't cut tails first, I kind of like it for the fact that you alredy got a nice staight line from the ply. Also I could see that being a pain in the bedonkadonk cause you'd have to finish the cut with a sawzall or hand saw. Personally I like to miter my facia and run sheathing right over the top.All I ever wanted in life was an unfair advantage...
I cut my tails when I cut the rafter. That works fine when the ridge and walls are straight,Sometimes with a rebuild or addition wee have to recut or shim them to straighten things up. I generally use a subfascia too, which is one before sheathing.
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Roger that. What is your subfacia? I once did a 12/12 with 2x blocking between the tails and than rough cedar facia as a finish..Lots of work but man was it nice..All I ever wanted in life was an unfair advantage...
usually 2x6 Why between the tails? no cutting to just slap it on the ends.
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Yeah I know, but the HO is old family friend/hobby builder(but I still built his roof) and that's what he wanted. But generally I'll do just a laid out 2x8, mitered at the roof angle on the top side, and in most cases now adays(shun me if you will) I'll shoot for the metal facia,facia flashing...what ever you want to call it(if it doesn't look quirky against the siding/soffrits).All I ever wanted in life was an unfair advantage...
Curious as to why in Maine and New England wide drip edge is used and other places in the country you can't even find it.
Strange - I have worked in FL, TX, CO, and now here.
I have always been able to use the good stuff - even found it the prevalent supply choice.
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So water running down the tarpaper ends up trapped between the edge strip and the fascia?
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DanH
Sorry. I have been busy. I am not trying to pick fights here. But I do want to learn how to do thingss better.
In your post you said.
With tar paper the drip edge goes under on the bottom edge, over on a gable end.
And I disagreed. I like to run the tarpaper under the metal edge at the rakes. I also run my Ice and Water under the metal edge on the eaves.
I think Piffin and Redford are right that I should go a step further and run a strip of I&W over the metal edge.
On the job in the pictures I ran the I&W 2" beyond the eave and into the gutter (as per the instructions on the box).
On this job the tar paper (15 lb) was run over the metal on the rakes and the eaves. Pitch was 3/12 on a downtown building. Shingles were 20-30 years old.
As you can see the water damage at the eave was bad enough to replace sheathing in some places and not very significant in others. We replaced 24' x 12" on the eave and a 16" x 4' piece on the rake. And 3 full sheets where they neglected blown off shingles for too long.
The water inflitration on the rakes would have been no problem if they had run the tarpaper under the metal edge. As it was it stained the edges and damaged the plywood in one area.
Even the eave (look for the gutter in the pictures) did not have much staining considering the tar paper was laid over the top of the metal edge. (Common practice here even today)
More pics in the next post.
Rich
Dan
More pics.
Rich
Edited 6/13/2008 9:45 pm ET by cargin
Cargin ....Dan said ....With tar paper the drip edge goes under on the bottom edge, over on a gable end.
You said.........I like to run the tarpaper under the metal edge at the rakes.
You're both saying the same thing! read what Dan said .....the drip edge goes under(the tar paper) on the bottom edge, OVER (the tar paper) on a gable end.
Geoff
geoffrey
Good thing I am not a proofreader.
I read Dan wrong several times. Sorry Dan.
I put dripedge over the paper rake and eave.
Instructions on the shingles say I am doing the eave wrong.
Now with Ice and water at our diaposal I think Piffin's method is the best.
Rich
Aren't you and Dan saying the same thing?
BTW: This is covered on the back of many packages of shingles.
Edited 6/8/2008 9:45 pm ET by Matt
waterhouse
I have wanted to ask this for along time.
The directions on the Winterguard (by certainteed) call for the ice and water to be installed over the metal edge.
Before we had ice and water I always ran the 30 lb tarpaper over the plywood and then installed drip cap.
Tarpaper over the drip edge left a clear opening for water or ice damming. I got burned once on a 2/12 pitch when i didn't know any better.
Now that we have winterguard that is adhesive and will seal (????) to the gutter apron, it has me wondering if I am doing it wrong.
In all the tear offs we do I have rarely seen damage to the roof eave extending more than 12". Almost always it is because of poorly done fascia. 1950s and 60s alot of homes in this area were built were the sheathing did not cover the 1x8 fascia. Hence the fascia would sometimes ride high and cause the metal edge to flatten out at the bottom.
Then this year we had ice damming like never before. That's another story.
Anyway most older roofs had the tarpaper over the metal edge.
Like I mentioned earlier (with the 30lb and metal edge) I reasoned that the main threat of water at the eave was from below, the opposite as the rest of the roof.
So until I am proven wrong (with BT just wait 10 minutes) I will continue to install my gutter apron over my winterguard.
Rich
Like Piffin, I bitch to the edge of sheathing, drip edge over that, then seal the metal back to the field with strips of bitch. When I'm done bitchin', the only thing the drip edge does is support the shingle overhang and provide a drip edge to shed water away from the facia or rake. I also run an extra strip of 1x (usually 1x1 or so) to keep the drip edge 3/4" out from the facia/rake boards. I see lots of roofers skip this step and put the drip edge right up against the facia/rake.
Here's what it looks like when it's done wrong. No drip edge, no overhang on the shingles. Water running right down the wood facisa boards.
New roof was put on Wed, all the damage fixed.