Newbie Needing Advice to Replace Subfloor

[earthmama9]

We are renovating a 1976 Overlander. The PO replaced the back 3 ft of rotten subfloor under the bathroom and we were SO sure we had a quality subfloor until now! *CUE THE SCARY MUSIC*

We removed the interior skins and found two areas of floor rot in the front of our AS. Both flooring is completely crumbled where the flooring is attached to the c-channel. There is an area about 18” along the c-chanel and 12” deep just to the left of the main door frame (if you’re looking at the door from inside the AS). See first picture.
There is also a rotten area just to the left of the seven way connector box in the very front of the AS. It’s about 8” (along the c-channel) by 5". See second picture.

I’ve been reading the forums for DAYS and still don’t have a clear direction to go. Once we build out the AS this whole area will be under a double bed with built in drawers so weight distribution will be theoretically pretty even (just in case that factors into anyone's advice).

Ideally we would leave the belly pan and wraps on and simply disconnect the c-channel from the floor and replace the entire front section in one piece. I started to remove the c-channel from the frame (picture 3) then thought, "HOLD UP!" However, it seems like some people are able to get one piece in easily while others try and try, get stuck, then have to cut it down the middle and splice from underneath.

I thought, if we replace the entire front, I could:
*cut out the existing floor
while the floor is out vacuum out all the gross insulation and dirt and address any frame issues
*install new floor (preferably in one piece)
*secure to c-channel with self-taping screws and elevator bolts.
*Cut one to two sections of the belly skin out underneath so I can access and finish securing the elevator bolts. See the fourth picture with where my hand-modelesque paw marks the spot.
*Patch up the belly (order the Al for belly skin and secure with buck rivets - or do I need to be able to access the back side with buck rivets?)

The other thought is drop the belly pan and patch the two spots individually. We want the path of least resistance and perhaps we are going overkill by replacing the whole floor. I'm stuck on these two solutions but perhaps and missing another route altogether.

Also, the frame is in excellent condition and the flooring is great everywhere else. Hence our desire for a shell on repair. I am trying, but failing, at posting pictures. Will try to do so in a follow up post.

Thanks in advance for your advice!

[Starstream]

So sorry you found water damage in the subfloor. We were very fortunate our '79 Sovereign was bone dry. There have been many vintage owners who have created threads concerning subfloor replacement. But if you're having difficulty sorting out all the info, or get lots of conflicting advice, don't be afraid to consult with professionals. We had our new axles installed at Bob Jones RV here in South Houston and ordered the new Dometic 434 stove from them, along with a few other odds and ends. They are a repair and restoration shop who will work on any RV, but specialize in AS. Sometimes when we run into something we can't solve, we consult with them. They're happy to answer questions, because we are clients and have referred others to them. If you start with them they might be able to refer you to a professional in your area.

A couple of things to consider, and you will have this with many projects. Take a step back and compare the amount of time doing a patch job takes vs. replacing entirely. It might be far easier to just replace the entire subfloor than to shoehorn in new plywood. If you're going to be putting in new everything else, why not start with a clean slate from the bottom up? As far as the belly pans are concerned, if you haven't done so, get underneath and take a good look at them. You may find there are some patches which can be removed to give you access. That was the case with our trailer.

It may or may not be a dirty secret, but as much as you think you'll stick to a budget, it ain't gonna happen. Restoring one of these old girls is a labor of love. Nothing practical about in the least. But that's why some of us love them.