Soft Spongy floor

[NotyetMHCowner]

Well crud. Our 2015 Montana High Country has developed a spongy floor at the entry area and back towards the kitchen slide for maybe about 4 feet and out from the wall about 2 feet. Im not positive where the water came from. The vertical trim right next to the entry door swelled up soon after buying the rig brand new. Our awning doesnt come all the way to the door for some bad design reason so when getting in and out during rain, a little water was let in so I thought that was why the trim swelled up.

Just about a month or so ago I noticed the floor was spongy feeling and started pressing around and saw that it was several square feet including under the kitchen slide. I crawled all over the roof and walls looking for something to caulk but didnt find anything. Pressing my fingers up against the black "tarp" floor above the tires sounds like rotted wood. I suspect that water from the tires has possibly slung up from underneath and started the problem from there. I wont know more until I start taking down the darco and inspecting from underneath. We have one more trip planned this year so I wont tackle that until we are done for the year and winterized.

I plan on making a rolling support for the slide and rolling it out of the way. Removing the kitchen island and pulling up the sheet vinyl (we plan on remodeling anyway so I guess there is no time like the present). Cutting out the bad part. Building back with plywood and 2x4s or 2x3s (whatever works right). Im not sure I will go bath with foam insulation (preferred) or fiberglass insulation. I may have to build supports underneath to support the seams. Leveling compound to smooth out the surface then probably sheet vinyl (even so plank flooring would probably be easier. We well replace the whole floor except for the bedroom. All carpet being removed in the living room.

I hate to have to do this to a 4 year old rig (should have been built right to start with) but this is the hand I was dealt. I will try to have pictures as we go. We are also going to either paint or stain everything white (not stark white but really light). The kitchen slide started struggling going in and out because the "slide bar" is sunk into the floor so the slide literally slides on the floor.

[sourdough]

I really hate to hear that. It's something that I think most of us worry about happening and hope like heck it doesn't. When I had a blowout in 16 and it tore thru the underside it was not comforting to see the construction of the bottom of the trailer. I've had the coroplast removed and replaced by the dealership 3 times now and I've spent the last few days under it repairing all the things they didn't do - just looking at all of it makes me very apprehensive about taking off to go to FL in a couple of weeks and we hope and pray we don't hit rain.

Wishing you the best of luck in getting the repairs made and hope all goes well. Keep us posted on your progress - it really helps the next guy that encounters the same situation....and someone will. Thanks.

[NotyetMHCowner]

I started digging into this job yesterday. I hope the I uploaded the 2 images correctly. Its looking like my water intrusion was from the door latch. The trim on the right side of the door was swelled up at the bottom (actually it started doing this within the first year of owning the rig). I cut away the coroplast underneath and everything looks dry and clean so I dont think it was coming in from below. Anyways, Im going to start building a frame on casters to remove the kitchen slide. Hopefully I'll have it out in a couple of days.

[NotyetMHCowner]

What sucks is the aluminum supports that are built into the floor. They are just under the 3/8" plywood, at the same level as the top of the styrofoam insulation. I will only be able to have a subfloor of 3/8" thick, otherwise it will not match the existing floor. I am trying to find the strongest material I can that is around 3/8" or slightly thicker. Possibly using 10mm engineered hardwood planks as a subfloor, or some kind of plastic or maybe even metal. I wonder if it would be a problem using 3/8" aluminum as the subfloor? I plan on laying the existing sheet vinyl back down.

I may have to add more joists, like 12" apart or less so the 3/8" doesn't sag when walked on. Sorry for talking out loud!! I'm literally figuring this out as I type.

I built the frame with casters yesterday for removing the slide. I still have to build the supports to sit on top of the frame and remove the slide topper.

[NotyetMHCowner]

Here is the support I have built to pull the slide. I'm a little concerned about how narrow the support is and how tall the slide is, but there is no other way to do this without a fork lift. I will pull it out probably tomorrow (Saturday) and see how stable it feels. If this doesnt work, I will have to find a repair shop to deal with it and pay out the nose.

[NotyetMHCowner]

I cut out the bad area down to the aluminum braces. It sucks that they don't give you but 1/4" to 5/16" to build a sub floor without having to build up the whole floor. I will add a couple of pieces of angle iron under the entry area to help support it better. I bought some 8mm laminated wood flooring to use as a sub floor under the sheet vinyl. I think it feels pretty strong. I'll post more after tomorrow.

[mikec557]

I started digging into this job yesterday. I hope the I uploaded the 2 images correctly. Its looking like my water intrusion was from the door latch. The trim on the right side of the door was swelled up at the bottom (actually it started doing this within the first year of owning the rig). I cut away the coroplast underneath and everything looks dry and clean so I dont think it was coming in from below. Anyways, Im going to start building a frame on casters to remove the kitchen slide. Hopefully I'll have it out in a couple of days.

Wow. That's a tough job. And it would seem to be a lot of water intrusion. How could that much have gotten past the door latch? Sideways driving rain? It looks like it would need a Firehouse of water to do that much damage to the floor. I know the paramount goal right now is to repair the floor, but if you change your idea on how it developed I would be very interested to hear that.

Mike

[NotyetMHCowner]

Sorry, I forgot to mention the strong smell of ammonia while ripping up the floor. I think one of my dogs has peed much more there than we thought and one of them is drinking it up. I do believe the door latch and our awning that wasn't attached right from the factory did contribute originally but then the dogs took over. Just my guess. I added braces above and below then installed 8mm laminated hardwood for a sub floor. I still need to use some sort of bondo or floor leveling compound to feather out the edges before putting the sheet vinyl back down.

[NotyetMHCowner]

Sorry guys, Im having a heck of a time trying to get these images rotated properly.

[NotyetMHCowner]

Lowe's sells DAP Flexible Floor Patch and Leveler that I think I will use instead of the Bondo. I will pick some up after work and see how that goes. It is much stronger now than before. I installed 2 pieces of 1" steel angle iron 1/8" thick between the stairs and floor to help support from below plus the 1" aluminum box tubing and angle iron above in the floor. Then screwed and glued the 8mm laminated hardwood. After leveling and smoothing out the floor, I will lay the sheet vinyl back down and start putting it all back together.

I took video of most of the process and will upload that somehow after I am done.

[flybouy]

Definitely use a flexible compound that states "made for plywood underlayment". A cement based compound won't flex enough.

[NotyetMHCowner]

The DAP flexible floor patch from Lowes worked really well. I got everything put back together this weekend. I am ecstatic about getting this job completed in 8 days. I really thought this would be a month or 2 job, (mostly because of waiting on special materials). The floor feels great. Its really solid, as good or better than before. The kitchen slide does not rub on the floor anymore. I also put silicone caulk down at the floor, wall junction to keep future dog pee from getting under the sheet vinyl and caulked the door latch incase that was a problem as well. I used some spray adhesive for the sheet vinyl and put some weights on top of boards to hold it down for a while because I had some wrinkles that happened from having the sheet vinyl taped up out of my way. When putting the slide back in, I had to raise it up a little higher because the floor was back to where it was supposed to be. That rolling frame is definitely the way to remove a slide if you have a level place to do it. I removed it and installed it completely by myself. I video taped most of the job and will get it edited and uploaded to Youtube or somewhere for people to see how to do it. I mostly video taped it because I could not find any video or pictures for that matter showing this type of floor and the repair or removing the slide (except for the one guy that I got the idea from on the frame with casters).

[mikec557]

That is awesome. Thanks for the thread.
Please post a message here when you get the video posted to YouTube. I'd love to watch it.

Mike