Forum Discussion

isonychia's avatar
isonychia
Explorer
Apr 24, 2018

found soft spot in floor

Hi,

We purchased a used travel trailer about 2 years ago.

Unfortunately, this year we found a soft spot in the floor.
It's about 12" x 12".

I have inspected the roof, slide outs etc many times and never saw any signs of failing seams etc. I obviously missed something.

The one thing we did notice upon opening the trailer for the season is it leaked inside from the AC unit.

The TT sits in a campground and never moves. We use it from April-July.

I was hoping for some guidance here.

I know I have to figure out the leak and do the repair. The repair is going to be difficult. I am skilled at carpentry and construction, so it's not the process that will be hard (I'm sure it will not be easy). It's the fact that the location is not close so I need to bring all my tools and TRY and anticipate what materials I will need. There is a local lumber yard so thats a bonus.

I guess I will start with the leak.

The AC unit is more towards the front middle of the trailer. The soft area is near the refrigerator and bathroom, near the back of the trailer.

Once I fix the AC seal/leak, I don't know how to track down the source of the leak that caused the soft spot. At this point I am assuming it's a roof leak or something in the bathroom. I know the water heater would leak into the bathroom through the drain plug FLANGE. So when I would reseal the anode rod or release the pressure after winterizing, the water runoff would enter the trailer through the flange. The water heater itself does not leak. (I don't think)

My idea is the following.

Can I remove the boards that seal up the undercarriage of the trailer and access the damage from there? I figure this will allow me to see the extent of the damage without tearing up the linoleum, carpet and removing the dinet couch etc. I also figured it would help me follow the path of the damage and maybe find the source/origin of the water entry.

I can only assume how the TT is built. I assume when I remove the undercarriage skin, I will see 2x4 type framing (not sure framing dimensions on a TT), insulation, pipes, wires and the subfloor. Does that sound right?

I have a bunch of other questions but I don't want to add too many at once.

Thanks,
iso

26 Replies

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  • campigloo's avatar
    campigloo
    Explorer
    Apr 25, 2018
    If it’s near the fridge check the little drain. It’s super flemsy tubing and can dry rot or get bugs in it. It should have some kind of direct route to the outside of the coach. Check it from the outside. It may even require removing the refrigerator.
  • isonychia's avatar
    isonychia
    Explorer
    Apr 25, 2018
    westend wrote:
    It sounds like leak prevention has been an afterthought. I'd suggest to do an interior pressurized leak test. That will reveal any structural leaking. You can check plumbing supplies and drains by operating them. Check tightness of plastic drains while you're there.


    An afterthought? Not really.

    An uneducated rv person, yes.

    I assume the pressurized leak test is for the plumbing system?

    I have been on the roof a few times and visually inspected all the lap sealant etc. I have never noticed any problems. However, if subtle pinholes can let in that much water, than that is something I cant prevent. In which case people should not bother inspecting all the seams on a TT roof and just keep putting on loads of lap sealant every year.

    Everytime I look at these seams it's impossible to tell if there are any pinholes. Between the bumpy texture of the lap sealant and dirt that covers things, pinholes can easily get unnoticed. Even after cleaning the seams it's tough to tell.

    The system these companies use to build these things is horrible.
    These TT have flat roofs, with a rubber membrane and there are 10 items penetrating the roof, antennae's, vents, AC units, solar panels, ladders etc etc. It's just a combination for a disaster.

    To make matters worse, they use luan roof panels, OSB subfloors and wood framing.

    I understand it's the nature of things, it's just a little annoying to try and prevent leaks when the system is not designed well.

    I take all the precautions I know how. I cant prevent them all if I cant see the problems. I visually inspect the inside of the trailer and always feel the walls and floors for any signs of wetness or softness. Thats how I found out the water heater drain plug flange lets water in from the outside.

    If pipes running underneath the subfloor have sprung a small leak and are wetting the subfloor, thats impossible to find. It's hidden.

    The AC thing is definitely my fault. After some researching I didn't know they were a major source of water problems. I didn't know I was supposed to tighten the bolts to make sure they have not come loose. (I don't move the trailer, it's static)
    I didn't know I need to dismantle it, remove it from the roof and check the seal to see if it needs to be replaced. Now I do.

    iso
  • isonychia's avatar
    isonychia
    Explorer
    Apr 25, 2018
    DutchmenSport wrote:
    Before doing anything, you need to figure out what your floor is made of. I had a drain leaking under the shower. The connection just came a little loose and needed tightening up, very simple. It does that about once every couple years. I figure its from the movement of the camper on the road and use.

    Anyway, I read your post earlier today and when I was under my shower jsut now to fix the drip, I took a second look at my floor and how its constructed. It's NOT what I thought at all.

    Mine is a sheet of linoleum on top of a 1 1/4 inch styrofoam sandwiched between 2 - 3/8 inch plywood sheets. That is laid on the cross beams, which are laid on the main frame.

    My camper is all aluminum framing, and all the walls are styrofoam sandwiched between paneling and outside luma. So, basically, my camper will never decay because of wood rot. There simply is no wood to rot!

    I have a soft spot in front of the kitchen sink, that's about a foot square also. I know it's not soft because of water. I do now know, it's soft simply because of my 230 pounds standing on it! But it's far, far, far from breaking, collapsing, or failing, and definitely not in need of any replacing.

    While I was there, I took some photos, namely so I can watch for any more problems with the drain pipe leaking (I cleaned up the pipe too) and can have a comparison for future reference. I like to document everything, especially with photos as the time and date stamp is on each one.

    Meanwhile, here's what my floor actually looks like under the shower.

    First photo is to give a bit of perspective, second photo is looking inside the hole right under the shower stall door.





    Thanks for the info DutchmenSport,

    I have the same shower and access door.

    Is there a resource that outlines the construction details of travel trailer brands?

    The spot is definitely a problem. It's almost a perfect circle and very soft. So I doubt it's going to be something other than rot.

    Any thought as to removing the undercarriage skin and accessing things from there?

    I assume there is possibly regular fiberglass insulation underneath. I also assume it will fall out when I remove the skin.

    Maybe I should just cut the linoleum back.

    iso
  • CavemanCharlie's avatar
    CavemanCharlie
    Explorer III
    Apr 25, 2018
    Maybe since it's such a small spot, and if it is not really soft you can fix the leak and don't worry about it. My floor in my 1993 TT has some soft spots but, I have the problem solved and since the spots are not hurting anything I just live with them.
  • westend's avatar
    westend
    Explorer
    Apr 24, 2018
    It sounds like leak prevention has been an afterthought. I'd suggest to do an interior pressurized leak test. That will reveal any structural leaking. You can check plumbing supplies and drains by operating them. Check tightness of plastic drains while you're there.
  • DutchmenSport's avatar
    DutchmenSport
    Explorer
    Apr 24, 2018
    Before doing anything, you need to figure out what your floor is made of. I had a drain leaking under the shower. The connection just came a little loose and needed tightening up, very simple. It does that about once every couple years. I figure its from the movement of the camper on the road and use.

    Anyway, I read your post earlier today and when I was under my shower jsut now to fix the drip, I took a second look at my floor and how its constructed. It's NOT what I thought at all.

    Mine is a sheet of linoleum on top of a 1 1/4 inch styrofoam sandwiched between 2 - 3/8 inch plywood sheets. That is laid on the cross beams, which are laid on the main frame.

    My camper is all aluminum framing, and all the walls are styrofoam sandwiched between paneling and outside luma. So, basically, my camper will never decay because of wood rot. There simply is no wood to rot!

    I have a soft spot in front of the kitchen sink, that's about a foot square also. I know it's not soft because of water. I do now know, it's soft simply because of my 230 pounds standing on it! But it's far, far, far from breaking, collapsing, or failing, and definitely not in need of any replacing.

    While I was there, I took some photos, namely so I can watch for any more problems with the drain pipe leaking (I cleaned up the pipe too) and can have a comparison for future reference. I like to document everything, especially with photos as the time and date stamp is on each one.

    Meanwhile, here's what my floor actually looks like under the shower.

    First photo is to give a bit of perspective, second photo is looking inside the hole right under the shower stall door.



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