I decided that I was going to tackle roofing my 2.5 car garage by myself, over a 5 day period. Well, after ripping off two layers of asphalt shingles, I started rolling out 30# felt. It's a 8/12 pitch and the roll would stay in place as I rolled it out and tried to secure it. I tried to get it as flat and as straight as possible while using 1/2 staples to secure it temporarily. It looked pretty good, and I put several staples in to prevent ripping the paper as I walked on it. After it was all in place, I went back and secured it with plasti-cap nails (1 1/4"). I thought I got the paper flat, but the next day I came out and there were a bunch of ripples in it.

Will this cause a problem with the shingles lying flat?

Again, I have....
#30 felt
Architectural 30 year shingles
8/12 pitch for a detached garage

I really don't want to redo the felt because I have to complete the project by myself!

 

This sometimes happens if the felt gets rained on or is exposed to a heavy dew followed by warm sunshine.

Just remember to use a chalk line to align your shingles and everything should be fine.

 

no one round here uses #30 felt on roofs, #15 felt is most commonly used. I think #30 wrinkles worse than #15. If you were applying it by yourself in short sections, that would probably explain some of the wrinkles too. Regardless of how well it was applied, it will expand and contract as the sun hits it, or if it gets wet from the morning dew. You will probably notice that the wrinkles appear worse at certain times of the day.

If the wrinkles are bad enough, they will telegraph through the shingles- especially since it is #30, it might not want to lay down. But, like wirepuller mentioned, it might be fine. Hard to tell since we can't see how wrinkled it is. I've seen paper jobs that looked perfectly flat in the afternoon look awfully wrinkled the next morning when it is cool and damp.

30 yr shingles might be heavy enough to weight the wrinkles in the felt down, but generally (in my area at least) #30 felt is not used under asphalt/fiberglass shingles.

 

I think you'll probably be OK as long as the felt isn't creased or badly bubbled. The stuff is pretty flexible.

Wirepuller - I'm not a roofer, but I've shingled a few roofs. I don't use a chalk line on a straight gabled roof. I just use the exposure tabs to keep the shingles lined up and I use a tape to check for square every 3rd or 4th course. It's a lot easier than snapping lines when you're working alone.