Webmaster said:
Thanks, Hog...
Yes, I have put a lot of roll roofing on in my days, and it served me well in those situations where you can't see it and you just need the lowest cost and quickest job - and even then we used the double coverage and cemented the seams.
As I said, there is rot and leakage, but since you can see daylight through the roof at a lot of areas, I suspect the rot is due to the fact that water has been getting under those shingle layers from above for years.
So what is this about exposure? I'm guess at that 4/12 since it looks like an easy walk-on. It has been shingled twice and I don't think it is 3/12
So I guess I will just follow the directions on the shingle package?
Do folks still use an upside down one along the rake......or do they use the starter strip that comes with some shingles?
Dang, I really hope I don't have to plywood the roof - because then I will question the rafters, and then there is no end. Maybe I will be smart and start by removing only one side so I see what I have in store. Then I can always give it a temp tar-paper while I stew about how far to go.
I hate to say it, but more info needed LOL.
I missed the part of it leaking in several ares. What are the rafters centers? 16" or 24"? What thickness (I'm guessing plywood) or if old enough planks?
The problem with a low slope shingle roof is, if the deck sags between the rafter, then it creates a small pool, and with not enough slope, the water looks for the lowest spot to run to. If the roof is leaking higher up from the eave, then ice & water shield will ohly help down there, but not where the leaks up higher are. If the shigles are deteriorated enough, the daylight you see might be from missing chunks of shingles and not necessarily the slope.
I suggest tearing off one side (prolly the worst side if there is one worse than the other, and see exactly what you are dealing with. Just get some 1" x 3" and a good tarp when done tearing off, and lay tarp out & nail the 1"x3"'s around the entire perimeter and vertically down the center in a few rows. that will hold the fort down until you decide your course of action. If I lived closer I'd be happy to come take a look & prolly end up helping. If you get stuck for help, I can prolly set a weekend away and come up.
Ok, if the holes are small, and you really just want to keep the cost down, just use some heavy gauge metal, like the stuff we make block off plate at HD or Lowes, and cut a few inches larger than the holes and nail the patches over the holes, then you can shingle over them. If the holes are large & numerous. You going to have to replace some wood. If the leaks are truly due to the low slope, you might want to consider Ice & water shielding the hole thing before shingling.
I have a feeling your going to find a mixture of really badly deteriorated shingles, with decking showing through & a few sag spots in the decking itself.
As far as 4" exposure. I for some reason think the shingle manufacturers did away with warranting the 4 or 5/12 pitches & less. Standard expaosure ( the part of the tabs you see) is 5", sometime 5-3/8". Depending on standard or metric shingles. As I said before on 4/12's it was spec'd to have a 4" exposure. Which means there is 1" extra from each shingle under the next two courses. Makes it harder for water to back up under the shingles and run under the tops.
If I am making this more confusing, let me know & I'll draw a picture. As far as the starter course (upside down shingle)at the eave or first course. Yes they are necessary. If you were to just put your first row or course on without a starter course, the seams between the singles would leak onto the decking because there is no courses under it.
The starter course is merely a shingle flipped upside down, cut 6" off the end before you run the first one. Don't forget to leave 1" hanger past the rake or side of the roof. This overhang keeps water from running under the sides as it runs down the roof. Some put a vertical run of shingles along the rakes also, I do not usually. Creates a hump when you run the courses over them. Leave an extra 1" at the rake also. Chalk lines really make this much easier.
You will pop your lines so that as your shooting your shingles, the exposure will be 4" instead of 5". I used to pop lines at every 20" to follow for 5" exposure, so every 9 " or 19" should give you 4" exposure. Its been a while, and easier for me to do, than explain. And verticals were always 29" & 35" from the side I start shooting at. which for me is right to left since I am right handed. This is for 3 tabs. If you use dimensionals, no tabs, means no pic lines, and less space for water to find. Dimensionals are easier to put down, & more easy to hide any oops. More expensive though.
You may have the rake mixed up with the eave. The rake is the side. The eave is where a gutter normally would be hung or bottom in other words.
Starters have never since I have known come with the shingles. If you are using 3 tabs, you just flip them over and use as starters. Or Ask the supply house if they have any junk bundles you could buy for starter strips. Sometimes they will give them to you. Color doesn't matter as they are not seen.
12' x 22' is only a 2.64 sq. Thats a very small roof. Order 3 to 3-1/2 sq for the job. For waste, hips, starters, and some left over for a , just in case blow off, or limb hit the roof. I'm sorry if I am bouncing all over, I am wooped, did my plumbing & put up another wall of 8" t&g;pine. Back hurts & just now finally chillin.
Ask any questions, I'll answer best I can. I'll draw a pic, whatever ya need. If it would be easier by phone, just PM me. I have free long distance. Well not free, but unlimited. What is easy in my mind from doing over & over, might not be as easily understood as I am thinking it is. However I can help, just lemme know.
When ya get a chance post a few shots of the garage. I can guess at the pitch with a good photo.