# 2.25 pitch roof...15 or 30 lb felt?



## MJW (Feb 7, 2006)

This stuff comes down to the codes and the inspectors. Up here, it would have to be full I&W. I'm not sure if that is everywhere though.

As far as "being ok", it probably would be fine with no paper at all (just being honest) if shingled correctly. That is not an option any more. If you think it will leak through your shingles, you better use I&W.


----------



## tpolk (Nov 7, 2009)

thought 2/12 was to shallow for shingles plus life expectancy is way down


----------



## my5sons (Oct 29, 2008)

tpolk said:


> thought 2/12 was to shallow for shingles plus life expectancy is way down


Under 2/12 is too shallow. Between 2 and 4 is ok according to GAF/ELK support. They require the overlapping like I said in my first post. They just don't say whether to use 15 or 30 lb. 

You are correct, life expectancy is down. For a 30 year roof, I can expect probably no more than 15. Likely 10 years. But this is more cost effective than trying to get a $15-20,000 metal roof. I'm saving money by doing the work myself and will be out about $3,000 for the entire roof job. Especially since they wanted $6,000 for 3 tab shingles, tear off and re-roof.


----------



## tpolk (Nov 7, 2009)

good to know about the pitch. are you doing metal valley? if so put a J stitch on the edge under the shingles. I'm big on 5/8 ply and 30# felt


----------



## tinner666 (Mar 14, 2005)

I&S shield for me. AND, I shorten the exposure 1/2" to 1", depending on the shingles. It's old school, and against all they teach today. Won't leak though. USE hdd nails! Not EG!


----------



## my5sons (Oct 29, 2008)

tinner666 said:


> I&S shield for me. AND, I shorten the exposure 1/2" to 1", depending on the shingles. It's old school, and against all they teach today. Won't leak though. USE hdd nails! Not EG!


I'm using GAF Timberline 30 Laminated Shingles (Architectural). Is there a way to shorten the exposure on these?

What are hdd nails? do you mean hdg? Hot dipped galvanized?


----------



## tinner666 (Mar 14, 2005)

hhd = Hot dipped.. Very dull and rough looking. The eg are bright and shiny and good for about 7 years. Sometime after that, they're so rusted, the heads come off and they can't be pulled normally.

I've shortened those 1/2 inch. THe water tends to drip off the slight overhang, and I believe they don't wick as moch water. The 1/2" less exposure gives a 3" headlap which can be key under an ice-dam.

Here's an example using slate on a 3-1/2"/12 slope.
http://www.albertsroofing.com/New Slate Roof.htm

Slate can be problematic because done incorrectly, you create mini fulcrums all over the roof. Which equate to pressure points leading to breakage. Old school of course.


----------



## tinner666 (Mar 14, 2005)

BTW. My own 2 1/2" shed roof is 3 tab, 4" exposure. Going on 16 years. My neighor followed suit with Timberline, 4" exposure, and Dutch-lapped his shingles. Same slope, going on 5 years. I don't think he even felted it. Not sure though.

"Dutch-lapped" No butt joints. Side-Lapped 4" to 6" where there was 1 layer thickness.

My house is done that way, but all that randomness increased material 25-30%. And not for the faint of heart. It's easy to make a mistake.

Many roofers think it voids the warranty. GAF, ELK, Certainteed, etc, all said it was no different than laps in a valley. Other roofers fall 50-50 calling it cool or me a hack. T-locks and others are lapped, and Timberline used the trend years ago.


----------



## my5sons (Oct 29, 2008)

Thanks Tinner, My 4/12 was done 10 yrs ago with 3 tab and they used no felt...did a crappy job, but it worked. I have no vents for bathrooms either. Installing those now.

I'm hoping you can help me find the waterproofing stuff. My home Depot and Lowes only sell the Premium GAF Weatherwatch underlayment with granules for s
teep slopes. $79 for 1.5 squares. I noticed GAF sells a standard waterproof membrane without the anti-slip stuff. I don't need the ant-slip with 2.25 slope, I'm just wanting to put waterproof down and start shingling.


----------



## Gary in WA (Mar 11, 2009)

Here on the West coast we call them HDG- hot-dipped galvanized. http://www.mazenails.com/whymaze.php

The others Tinner said are the last ones here: http://www.mazenails.com/hdgspecs.php

If you use any paper, be sure it's the right one: http://www.fortifiber.com/pdf/fortifacts/fortifacts_ask_vs_felt.pdf

Be safe, Gary


----------



## tinner666 (Mar 14, 2005)

Any is better than none. I go with whatever my supplier has on hand, and it's often Tamko. The roof is what's crucial. Mess it up, and it won't matter what's under it. I recently repaired 2 that had Grace under the shingles, on one. The other was under slate.
Ask the supplier if their sealing properties are equal.


----------



## my5sons (Oct 29, 2008)

I can't find Hot Dipped nails for my Milwaukee Pneumatic Nailer anywhere around here...

Grip Rite sells GRCR3DHDG, but I can't even find them online.


----------



## tinner666 (Mar 14, 2005)

I quit using nail guns in the 80's and no idea how coil nails are rated. If they're not bright, they may well be ok. Sorry I can't be more definitive.


----------

