This picture is also shown on the ponding page.
The brown stains are where the water ponds up when it rains. The wrinkle is circled in red. This particular wrinkle is not worrying me. If it doesn’t have fiber tape added on top of the wrinkle to support it, then just keep an eye on it.
Again, these wrinkles don’t cause me great concern. I did have a roof coating manufacture look at this roof and several others. Their opinion is a little more harsh than mine, and its easy to say tear it off and start over. There is no liability at all for them to go the most conservative route. If this was my roof I could get another twenty years out of it with preventative maintenance and a new coat every four years or so.
The red circles show what your looking for on the top of wrinkles that are going to the next – bad – step. If you click on the picture and enlarge it you can see where the wrinkles have cracked. These need to be taped and patched now.
Another roof the coating manufacturer said this roof needed to be torn off and re-done. It was improperly installed about 10 years ago and not enough tar was used to hold / glue it down to the plywood. In some spots you can feel the paper floating over the plywood as you step on it. It feels like stepping on cardboard that’s bowed up a little bit. There is a kind of pop sound and you can feel it move down a little in certain spots as you walk across it. The reason I don’t believe this needs to be torn off is of the very small likelihood of the wind getting under it and flipping the tar paper over. On a house with eves its common for a roof in great condition to flip up like a bed-sheet if the wind is blowing strong enough. I’ve NEVER seen this happen on roof with parapets (walls) around the edges. In other words if you can easily afford it and want the absolute minimum risk, then definitely tear it off and get a new one installed. If it were my parents or brothers house I’d tell them to keep an eye on it and with maintenance it will most likely not be a problem.