RV Repair: Reroofing, doug fir, two by twos

Question
I have a 28ft 1991 Wilderness Travel trailer, It has some soft spots in the wood around the edge were the rubber roof material rolls under the aluminum trim . We are looking to reroof the trailer Is it necessary to replace the whole section of wood or can I cut out the soft wood and splice into it . Also is there a source that has info on this project, the guys that will be helping me are quit knowledgeable in construction but not on RVs

Answer
Brad Hello
Well that can be a big job . I've been doing them for 28 years and no two are the same, but then again they are.
The amount/extent of wood rot is the problem.
"You can't attach good wood, to bad wood" and you'll need to remove all the bad wood to solve the problem.
Its not a complex issue, we're not dealing with the space shuttle. It is just a procedural issue...step by step in the right order.Pull the skin, excise the dead wood, dry it out replace the insulation, measure, measure, measure. If you can splice it, then do it, but its harder to get strength with a splice. On two by twos we Siamese the stringers together.
The factory was skimpy on framing but you don't need to be. Use as much wood as you want,if it fits. They used 2x2s and 1 bys ,pine, I use Doug Fir, no need for Redwood. What do you want it to do....last forever??? ..
I am not aware of any dyi on RV roofs.(Maybe I should write one). But with the help of your construction buddies (and beer) you can do it.
When your done..seal it ,seal it, seal it.
Hope I helped.

Thom