This looks like a good time for me to enter this conversation because Fiona’s roof looks very similar to mine but hers is way worse. My condolences to you Fiona.
You mentioned sheathing should be checked to make sure it’s nailed down flat to the eaves. The sheathing on my reroof is not nailed down flush to the board in numerous areas and your reasoning makes perfect sense. Thank you. Not only is my roof lumpy but it doesn’t have a consistently smooth slope. Some areax have a different slope them others and you can see it through the shingles. This leads me to my question concerning other possible reasons for my lumpy roof. I should mention that hardly any of the sheeting was replaced on my roof or the boards that are members. From the underside you can see mold and numerous wet marks and possible dry rot. When they put the sheeting on instead of replacing any of the dry rotted or damaged or warped boards it looks like they just shaved the dry rot off the top of the board or Dug the chunk of dry rot out… since the end result makes these boards different widths in places wouldn’t that also be a cause for the board not being nailed consistently flush? It appears that there’s been an awful lot of two-by-fours that were shaved to save their expense. It’s very obvious the boards were shaved and dug into because the painted wood shows the exposed would that was shaved clearly when you look from underneath. No attempt was made 2 fill the gaps with any type of wood filler.
My last question on this topic is this. The limited amount of sheathing repaired was replaced with plywood in some areas and then OSB in others. Wouldn’t the replacement have to match the original wood in thickness? If they’re not the same thickness could this be cause for a lumpy roof or inconsistent slope? There are so many places that the roof just seems to cave in and have waves and ripples much like Fiona’s.
Maybe I should have started a new topic but I thought this was in the same lines of your discussion so I apologize if I’m out of line on this I’m exhausted and this just seemed easier and more appropriate to me at this moment
Thank you Fiona, for your post.