# 12/12 pitch and vertical underlayment???



## mtmtnman (Sep 18, 2009)

Good morning folks. We are in the process of building a cabin for a client WAAAAY out in the sticks. No inspections other than Electrical and plumbing. Roof is a 12/12 with 2 dormers on the front. Ridge is 38' from the walkout basement at the tall end and 28' at the short end. Eve height varies from 14' to 22' Ground slopes on both sides. No way to get a lift on site due to where the house is being built on the property. Roof will be standing seem metal 26ga. My question is due to the roof pitch can the underlayment be run vertical with a 6" overlap? Using Tiger Paw synthetic. It would be MUCH easier and safer to do it this way and with a 12/12 i see no real issues but am i missing something? Also considered running Ice & Water over the entire roof vertically. Problem with running it horizontally is of course the pitch for one and the length of run. We are 44 feet from end to end and it would take AT LEAST 3 people tied off to lay this stuff out! I keep saying never again on 12/12's.....


----------



## mtmtnman (Sep 18, 2009)

lol, Can't edit my mispelling in the title. Fat fingered they keyboard....:whistling


----------



## ZachNewberry (Oct 1, 2014)

I'm curious to hear other responses, I don't think this is a good idea, If the metal leaked water would more easily find its way into the seams. Even with a vertical half-roll lap I think water would still trickle in and over if the metal failed. Also tiger paw strictly states Parallel to the eaves http://www.gaf.com/Residential_Roof...er_Paw/Tiger_Paw_Application_Instructions.pdf 

Personally, The only time I run underlayment vertical is typically when a hip meet a valley and the entire surface area can be covered in 1 vertical sweep. Leaving the underlayment wrapped over the hip on one side and terminated over the ice and water on the other.


----------



## 1985gt (Dec 10, 2010)

I've heard of people doing it with #30 felt and double coverage. I don't think i would though personally.


----------



## Warren (Feb 19, 2005)

We have never run any roofing paper vertically. We have done pitches as steep as 24/12.
12/12 is normal for almost all of the houses we frame.


----------



## Tom Struble (Mar 2, 2007)

i would agree with keeping horizontal but i wonder if the seam could be taped..


----------



## mtmtnman (Sep 18, 2009)

Warren said:


> We have never run any roofing paper vertically. We have done pitches as steep as 24/12.
> 12/12 is normal for almost all of the houses we frame.


I have done a few but NEVER one where i couldn't get a lift to. This whole roof is being done entirely off a rope and harness.


----------



## ZachNewberry (Oct 1, 2014)

mtmtnman said:


> I have done a few but NEVER one where i couldn't get a lift to. This whole roof is being done entirely off a rope and harness.




No toe-boards / Jacks to help on underlayment application? Sounds like a good job to implement some scaffolding and walk picks. Make a highway around the whole damn house 

I also saw some outrigger type deals for walk picks that mount to the exterior wall and go out enough to get your pick past the eave on new construction. I think the crew had them custom made I was drooling at the simplicity of them from across the lake at our job site.


----------



## jlsconstruction (Apr 26, 2011)

Does your underlayment have it as an option in the installation guide.


----------



## EthanB (Sep 28, 2011)

Not a roofer but what's your biggest obstacle here, aside from the pitch? Rather than the expense of I&W or the risk of installing against manufacturer's specs, couldn't you just cut the underlayment into shorts on the ground so 2 guys could handle it more easily?


----------



## mtmtnman (Sep 18, 2009)

Biggest problem is the time of year. Mid 30's every day and i have found no shoes that have any grip. We are going to attempt to put Synthetic on from the top down horizontally tomorrow leaving the bottom 6 inches un-secured in order to flip it up and over the next lower level. Did a dormer today and COULD NOT stand on the ice and water at all. Guess i need to take some more pics tomorrow..............


----------



## bkb0000 (Feb 1, 2009)

Methods vary by region and roofer, but there's really nothing wrong with running the underlayment vertical. If your metal roof leaks due to a workmanship error, the underlayment isn't going to save you. If your roofing system requires waterproof underlayment to handle occasional leaks from ice or storm, then you should be using a self-sealing underlayment, in which case it would also be OK to run that vertical- because it's sealed seams.

I haven't done it in years, but back when I was apprenticing, we would run pretty much anything over 8/12 vertical. Here in Oregon, the underlayment's primary function (from the roofer's perspective) is just drying the roof in for the duration of the project. We had plenty of vertical felt sit under rainstorms without any problems- at those slopes, water doesn't wander much, it just tends to roll straight off, even on wet, wrinkly felt.


----------



## mtmtnman (Sep 18, 2009)

Well i have thrown in the towel and hired a young buck to finish this. I went down on one knee between the gables yesterday HARD (damn 1/4" hose swung under foot) and of course finished the day anyways. Today i can't walk. I guess over 40 year olds don't belong on a 12/12. Thank GOD for a good harness! How you guys that do these pitches day in and day out i will never understand......


----------



## dDubya (Feb 1, 2013)

Toeboards!! My Dad is 61 and he prefers a 10 to 12/12 over a 6-8/12 any day because he has a board to walk on rather than stressing his knee's and back. Sometimes he mentions putting down toeboards on 5-6's and I look like :blink::blink:


----------



## klintala (Aug 2, 2014)

Obviously you should never have to rely on your underlayment, so in theory you should be able to get away with whatever you want, especially if you're considering using ice and water.

That being said, I would lay it horizontal.
Use ladder jacks to get your first row on, then roof jack your way the rest of the way up. It sucks, but at least it will be done right.


----------



## midmich (Dec 16, 2014)

There should be no problem running it vertically if you are installing a Standing Seam metal roof over it. If it were asphalt I would be retracting my words. 

We have builders and contractors alike that do this all the time. The only reason that you have to use synthetic felt under a metal roof is for condensation from the panels. If you want to be safe use some butyl tape at the overlap and that would surly keep things water tight. Or to be really safe you could use Hi-Temp Ice shield on the entire roof.

But it is on your name so do what you think is best.


----------



## hardtroofing (Jan 23, 2015)

My thinking behind this is, why not spend the extra time to run horizontal knowing how much metal sweats. It is hard for me to go against the grain with something new especially on a project that you can not go back and make changes. 
I do like the idea of tyvek tape I would at the least tape it.
Good luck and be proud. This roof sounds like it is going to be a cool roof to do!


----------



## Mr Latone (Jan 8, 2011)

Well, maybe you got the whole felt thing straightened out then?

How the heck were you planning on doing the metal roof if just laying the underlayment was such an issue?

I guess I am being a dick about it, but the felt and i/w is surely the easy part.

So is the job now subbed out to the 'young buck' in its entirety?


----------



## Maxon100 (Feb 11, 2015)

I've seen felt and other underlayment rolled vertically on steep roofs but I wouldn't recommend doing it. From your picture of the house it looks like a perfect job to set up some scaffolding, if you don't have any just rent it. 

http://stormproofroofing.org/


----------



## Knight-Builder (Feb 19, 2015)

Here's what we did recently on the project we're working on (apologies if anyone got the shivers looking at that miserable white stuff)

The pitch is also 12/12, with profiled metal sheets being the final layer. Scaffold erected up to 1 foot below eaves (out of image), then we worked our way up with synthetic. We strap/batten under all our metal, so we were able to create a ladder of 2x4s (spaced for 1.5" Blue SM as can be seen) as we went up - roll out one course of underlay, strap, climb up, repeat. 

It's trickiest for the guy unrolling, so naturally I elected myself chief staple master :thumbup1:


----------



## mtmtnman (Sep 18, 2009)

Mr Latone said:


> Well, maybe you got the whole felt thing straightened out then?
> 
> How the heck were you planning on doing the metal roof if just laying the underlayment was such an issue?
> 
> ...



My bid was for framing and dry in. I'm too busy to do anything start to finish. Not enough money in it to screw with metal roof when you don't do it every day. Another company is going to install standing rib on the entire home for $10,500. Metal is ALL they do.


----------



## mtmtnman (Sep 18, 2009)

Maxon100 said:


> I've seen felt and other underlayment rolled vertically on steep roofs but I wouldn't recommend doing it. From your picture of the house it looks like a perfect job to set up some scaffolding, if you don't have any just rent it.
> 
> http://stormproofroofing.org/



got PLENTY of scaffolding but only took me an hour to do the eves all the way around off of 2 ladders. Trying to get scaffolding stable on frozen ground would have been an all day job even with adjustable legs which i have plenty of. The monkey i hired papered the entire roof less the 7/12 section which i did for $350 including 1 hour travel from town.......


----------

