Replacing wet bay floor.

[mbishop10]

Hi everyone. We're newbies. Don't have a lot of advice to give yet, but we could sure use some help.
At the end of our "get to know our coach" camping trip we had some trouble with our macerator. Investigating the macerator led to pulling the wet bay tray which led to pulling the water tank.
Basically, the chip board was gone below the water tank and the wet bay. Really didn't want to rebuild the wet bay floor from scratch, but that where we're at. The chip board has been vacuumed out, the foam luan layer removed, as well as the aluminum sheeting.
Time for the rebuild, here's the plan:
1. Scrape and treat the rust.
2. Paint the frame.
3. reinstall or preferably replace the aluminum sheeting. Not sure where to get this, and what to stick it down with. It had what looked to be a thick double sided tape.
4. Install replacement foam board. Thinking about the Super Tuff-R Foam Insulation from Home Depot. The blue stuff.
5. 1/2" pressure treated ply wood.
6. Still debating about putting the felt back down or putting down a 4 * 8 piece of pvc paneling. And, possibly fashioning a drip tray of some kind. Anyone done this?
Haven't found the source of the water. The rotted wood and the carpet were moist but not dripping wet. This is a 10 year old coach and there is evidence of a past leak and some repairs.
What do you think of the plan. Are the materials such as the p.t. ply and the foam board, OK?
Any thoughts or suggestions would be appreciated.
Thanks

[Papa_Jim]

["007"]

Welcome to the forum.
Here is a Brochure and Owners Guide for your coach.
Are you talking about the wet bay floor as in this link with pictures or the floor under the leaking water tank that destroyed the floor under it.
Your on the right track if its under tank aluminum you can get a Home Depot along with sealants, foam board, plywood and rubberized spray to undercoat the replacement floor. They may have a good sticky double sided tape to hold things together or a good bonding liquid nails compound.
The new floor slips under tank with sheet metal, foam, plywood to support the tank, some tanks are blocked in with wood blocks for holding in place.
You want to seal good so cold air can not penetrate the tank areas that are heated for winter travels.
You did fix the leaking tank so its now dry? If not I would try and find could be a pipe fitting that needs tightening or a overflow tube with loose clamp at tank top or if you have split tanks both sides of chassis rails like mine a 1 1/4" pipe between them to connect.

[soricobob]

I'm just assuming you're fixing the leak before you do anything.

[mbishop10]

Posting a couple pictures. One of the damage and another of the ongoing repair.




We're still investigating the possibility of a leak. As I stated in my initial post, there is evidence of a previous leak and repairs. The water pump looks new. The rotted area was damp, but no standing water.
While we have the tank out we will try to hook up to city water and operate some of the systems to see if there's any leak.
One thing we were thinking about is condensation on the tank. Is that a common problem?
So far we treated the rusted metal with Jasco and just finished painting.
Thanks 007 for the links. I think they will be very helpful.

["007"]

The damaged area looks to be near center of bay, some bay door seals have cause problems over the years which allowed water to enter behind door seals into bay and some coach rear wheel wells were not sealed completely allowing water into compartment bay's when traveling.
Looks like your progressing well, your idea of filling water in tank would be a good thought before moving on you still have particle board in the good part of bay.
I wonder if Newmar on newer coach's stopped using the particle board ?

[slowmachine]

That looks like a great spot for some aluminum diamond plate. Probably needs a bit more structural support, but won't ever rot.

Mike

[tednruthy]

Check the wheel wells. On my prior coach a 2001 DSDP I had a leak and replaced my wet bay floor due to a vertical crack in the lining Newmar used when they built the wheel well. The water got into the wetbay and the particle board wicked it and it destroyed the floor. I got the sheet aluminum from a sheet metal shop cut to size since the big box stores only sold flashing that was too narrow. You need a piece just smaller than 4 ft by 8 ft.

[mbishop10]

Thanks for the ideas! I will check the wheel wells and seals carefully.
The diamond plate idea sounds interesting, but expensive. We certainly want to put it back together better than it was. When I head to the sheet metal shop I'll check that out as an option.
We've painted, so now it's time to get our rebuild materials together.
I don't think we want to put the carpet/felt back down. Any problems with that?

[mbishop10]

After the Tampa Super Show, got back to business...
I got a bit of an education about aluminum and the different grades. What is going in is grade 3003.040". I'm not sure if it's the same grade as the original, but it's thicker. Cost was about $80. I probably could've gotten it cheaper but I got it next day and cut to size. Installed the aluminum with a bead of silicone caulk.

Attachment 84054

Attachment 84055

Next came the foam insulation- needed about a 1 1/4" of foam, so glued together a piece of 3/4" and 1/2" foam board. Topped the foam with 1/2" pressure treated ply wood. Unfortunately had to cut the ply in half to get it in- otherwise I would've had to remove the black and grey tanks.

Instead of carpet, added a sheet of PVC board. Would've liked to have some sort of tray but cost was prohibitive. So instead added 4" PVC strips to sides and caulked the joints. Won't contain a flood but may slow water from getting down to the ply.

Screwed everything down with about 6 screws and a dab of silicone.

Under the bay, added another bead of silicone to the aluminum panels and as soon as the weather permits, will spray a coat of undercoating.

Attachment 84057

Meanwhile, filled the tank with water and did not detect any leaks. Hooked up to city water and pressurized, did not detect any leaks from the sinks or commode. Haven't checked out the shower or washer/dryer. Didn't see anything cracks around the wheel wells. I don't know where else to check so I guess I'll reinstall the water tank and the other connections.

The original Newmar tank monitoring system was replaced with a See Level system. Have no idea how any of this was hooked up so I'm headed back to the classroom. Should've taken pictures-

And the macerator repair kit just arrived.... which was the genesis of this project.

[Sky_Boss]

Thanks for the update.

["007"]

If you have a center bath your shower could be leaking, at the base of shower floor there is a vent for return air to furnace, if the drain pipe is loose could be your water leak.
Remove the vent to get access to the drain.
Your picture do not load, will look for them, for you. YOU NEED TO RELOAD THE PICTURES. If you reload I will move to post.
Thanks for the follow up good job well done.

[mbishop10]

Here's the pictures that I meant to load.

["007"]

Thanks find where they are, check the shower fittings.?