Need Help with Floor Damage

[MSL]

I apologize in advance for the long post. Also, is this posted in the correct forum?

My 2019 Sport 22 has developed floor damage; low spots (about ¼”) in the center of the aisle in the area of the microwave and sink (see attached sketch). At least I believe there are low spots, and not high spots; I used a 4 ft level. I assume it’s damage from water, but I’m not sure when it might have happened, although it probably came in from the skylight. In June, when we were on the Gaspe Peninsula, we stopped at one point during a very heavy rain, and there were several drops of water (no puddles, just drops) on the dinette table and floor, and I could see drips at the skylight. The next day at the campground I borrowed a ladder and everything looked normal, but I could see that the tape used by Airstream to attach the skylight was not adhering in some places. (In my opinion, this is a ridiculous way to install the skylight, which has a bottom surface that isn’t very flat to the rigid, flat flange of the apron.) We were gone for another week at that point, and we never saw any more water dripping in spite of it raining and driving through some rain; rain that was not nearly as heavy as when we experienced the leak.

At the time, I assumed only a small amount of water came in through the skylight, caused by the gaps in the installation tape coupled with the heavy rain while driving. I never sensed from anything else that more water might have come in without me knowing/seeing. I believe the skylight apron kept water out when the trailer was stationary (and during mild rain while driving).

Before our next trip, I used 3M Extreme Sealing Tape (had to use multiple, overlapped strips because I could only get the 1 ½” width) to seal all the way around the skylight, as well as the vent/installation holes. This was done around the beginning of September, and still looks very good.

Later in the fall I noticed a dip in the floor. At first, I wondered if I could have done something when I installed the lift kit (in August), but didn’t see how this could be possible; I jacked/supported front and back under the frame. Then one day when it was below freezing and I walked on the floor, I noticed what sounded like it could have been ice crystals crunching between the slightly raised vinyl flooring and the plywood in the area of the floor that isn’t flat.

Since then, I’ve looked everyplace I could relatively easily to see if I could detect moisture or evidence of a leak. I pulled the access panel below the sink cabinet, looked in the water heater/electrical access area, looked in the area below the wardrobe area where the water pump is, pulled the dinette panel (below the cushion) on the street side, and I found nothing.

So, I assume more water came in through the skylight than I thought in June, and it took a while for it to soften the floor. (The floor still sounds “hard” when I knock it with my knuckles.) I really don’t think my a/c condensate line is blocked; I’ve never had water dripping from the ceiling/walls, and I’ve seen it coming out of the tube at the wheel well. (I was unsuccessful trying to pass a trimmer line up through the tube from the wheel well, but I think this is just due to friction at the bend in the tube where the wall meets the roof.)

I’m thinking of trying to repair this myself as I’ve had negative experiences both at my dealer and at Jackson Center. (I’ve been to JC twice for warranty work where they attempted to seal a leaky exterior door, and I just noticed it leaking again the other day. This leak drips between the two sheets of aluminum that are riveted to the inside of the door; the drips come from behind the top piece to the inside surface of the lower piece.) My thought would be to replace sections of plywood that are damaged. My hope is that I could remove cabinetry from the front end of the trailer to the bathroom, and roll the vinyl flooring up so it could remain in one piece.

I really need some help with this. Here are my questions:

1. How do I ensure I don’t have a leak someplace still?

2. Can this repair wait until the summer? We’ve got a trip planned to the Pacific Northwest leaving the 1st week of May and plan to be gone around 7 weeks. I know things like this shouldn’t wait, but I’m afraid, especially with New England weather, that I won’t be able to get the trailer travel-ready if I start now, and I haven’t yet even researched how to go about this, or which materials to use, etc.

3. Am I missing a way to access the floor to confirm it is water damage? Maybe this is a waste of time … what else could it be?

4. Is the dinette pedestal attached with wood screws into the plywood? I’m thinking I could remove it and cut a slit in the vinyl to examine the floor. Right now, the pedestal seems very solid.

5. Does Airstream ever use shims between plywood and frame? Is it possible a shim fell out? Maybe happened when I installed the lift kit.

6. Does anybody know reputable service people in the New England/New York/New Jersey area that they would trust with this type of job? How much might something like this cost?

7. Are my repair thoughts (paragraph just above the list of questions), i.e. replace sections of floor and keep the vinyl intact, reasonable?

8. Should I light a match to this thing now?

Just kidding with number 8, but this has really taken the wind out of my sails; very disappointed in Airstream design and manufacturing. We love traveling in this thing, and aren’t ready to give up yet.

Thanks in advance for the help! This forum has been invaluable several times already!

Mark