My house is in CA (USA, we don't have many stroms / heavy winds) and i am undergoing a re-roofing project. House is about ~65 year old the current "plank decking" looks in decent condition.
Is it a good idea to put a OSB on top of it to make it a "SOLID SHEATHING" before putting the singles ?
My roofing contractor told that very few people chooses that option (1/100) or so.
Cost of adding OSB (solid sheathing) is ~20% higher (2K $). Is it worth the investment?
I already have adequate attic insulation and my question is primary related to longevity of the new roof.