Soft Spot In Tub Floor

[FlyboyTR]

2010 3023...

As we continue our work on our NU2US TM, while doing the shower mod (similar to what we did with our old TM) I quickly noticed there is a VERY soft spot on the shower/tub floor. It is located on the forward side of the tub drain. When I say soft...it will easily flex 1/2" with just a little foot pressure. Everywhere else is rock solid.

I'm sure that at some point this would have the potential to cause a major problems with the drain plumbing, or even cracking the tub floor.

I may be able to access this area through the backside of the outside shower. For now we will just be very careful not to step anywhere near the drain. But, in the near future I will have to dig into this.

If you know about this type of problem, please provide details and your modification/repair. Thanks!

Travis :)

[commodor47]

Given the rat infestation, they may have removed some of the cushioning material from that section, under the tub. Where is your bathroom vent located? If it is hidden behind the left side of the toilet, you may want to remove the toilet for access. That might give you room to check the tub area in question.

Dick

[Kidkraz]

Might I suggest pulling the outside shower/faucet. When I pulled mine with the idea of using that side for my cassette water connection, it gave me a decent view of the area under the tub. Good luck.

[FlyboyTR]

Dick,
Yes, vent is located between Tumbler and the tub. That is certainly an option. I hadn't given any thought to this problem being caused the rats...but considering what I have found so far, ANYTHING is possible! Thanks!

Kid,
Since I do want to check the plumbing...the Outside shower may be my first shot. Thanks.

Travis :)

[Kidkraz]

I don't about you, but when I pulled mine out, I marked the hoses, so I know which is hot and cold. Once disconnected.......it gets ugly. I'm a belt and suspenders kinda gal.

[FlyboyTR]

I don't about you, but when I pulled mine out, I marked the hoses, so I know which is hot and cold. Once disconnected.......it gets ugly. I'm a belt and suspenders kinda gal.

Thanks for the input. Always better safe than sorry!

[90Carat]

On my 2009 3023, I noticed that there is a crack right around the drain of my tub. It doesn't look like there is any support under the drain area. I could see daylight through the crack. Since I just found the crack, and we don't use the tub, I haven't torn it apart more to see what's doing.

[90Carat]

I took a few minutes and crawled under my 2009 3023. What is supporting that area of the drain? Nothing. Underneath, there is a plastic box that has the P trap for the shower drain. Mine was soft enough that at some point recently, it cracked. The good -ish news is that it looks like I should be able to pull the box, and reinforce the drain area with additional fiberglass support from the bottom. Fix and seal the crack on top, and should be good to go. Not a pleasant job, but should do the trick. We don't use the shower, so it is low on the priority list.

[FlyboyTR]

Sorry you have a crack. Thankfully I got to mine fore that happened. We use the shower when traveling.

[Wavery]

I'm not sure why I am just now seeing this but if you haven't attacked the issue yet, here's an EZ fix.

I recently removed the outside shower box (for a different project) and reviewed the under-tub area. I remembered that our tub had a soft spot where yours is. I noticed that there was a gap between the tub bottom and the floor. I got a can of that expanding foam and filled that area. I left it set for a few days, then I trimmed the excess foam so that I could get the outside box back in. I tested the tub and it's solid as a rock.

Hope that helps.

[FlyboyTR]

I'm not sure why I am just now seeing this but if you haven't attacked the issue yet, here's an EZ fix.

I recently removed the outside shower box (for a different project) and reviewed the under-tub area. I remembered that our tub had a soft spot where yours is. I noticed that there was a gap between the tub bottom and the floor. I got a can of that expanding foam and filled that area. I left it set for a few days, then I trimmed the excess foam so that I could get the outside box back in. I tested the tub and it's solid as a rock.

Hope that helps.

Wavery,
Thanks for the info. I was able to add some bracing under the tub and it did help...but the next time I have the outside shower removed, I will follow your lead with the expanding foam. Thanks!

Travis

[Bill]

When I had this problem on one of my earlier TMs, I glued some wooden blocks to the floor under the tub, and then topped it off (filled the small remaining gap) with a big glob of foam. Try to find some low expansion foam. The softer ones may still allow more bounce than you like.

Bill

[FlyboyTR]

When I had this problem on one of my earlier TMs, I glued some wooden blocks to the floor under the tub, and then topped it off (filled the small remaining gap) with a big glob of foam. Try to find some low expansion foam. The softer ones may still allow more bounce than you like.

Bill

Thanks. Great point about the low expanding foam!

Travis

[Deb Mac]

Having just done a repair to the P-trap under the tub, I noticed in my labours that there was a lot of flex around the drain as I was trying to get the trap disconnected and the drain removed (another tale!).
Fortunately I didn't crack anything, and I have the P-trap repair finished.

Not having used the tub yet (new-to-me trailer last summer, haven't used the shower yet, and still working on it) I wasn't even aware of it. Glad to have found this thread (wish I had found it BEFORE I had finished the work on the P-trap repair :( ). Going to have a look under there while I have the trap cover off and see if I can address the problem from underneath without removing everything I have just put in. If not, I will just be very judicious when I use the shower, and avoid the front end until I can get the outdoor shower pulled - have to do that anyway at some point - couldn't get the old, stiff shower hose back into it's cubby when it came time to winterize and then close up. So I had to cut it off in order to close the door.

Followup…. Went back and checked. My tub is actually pretty solid. Right over the drain is a little soft, but not overly so. So looks like I lucked out there.

[Bill]

Soft tub floor is a problem that several of us have experienced. You may be able to get easy access to the bottom of the tub by pulling the converter out of the wall. That's what I did. Then put the block on the floor under the soft spot. Make the block almost but not quite tall enough to touch the bottom of the tub, then squirt a lot of foam into the gap. Use a minimally-expanding foam.

Having gone through what you just did with the tub drain, you might want to mask off the area right around the drain, so you can do it all again if you need to.

Bill

[FlyboyTR]

Having just done a repair to the P-trap under the tub, I noticed in my labours that there was a lot of flex around the drain as I was trying to get the trap disconnected and the drain removed (another tale!).
Fortunately I didn't crack anything, and I have the P-trap repair finished.
.

Deb,
As usual on this Forum, I received a lot of good advise. If possible, read back through everything. There are several ways to access this area! Good luck!

Travis

[Wavery]

Deb,
As usual on this Forum, I received a lot of good advise. If possible, read back through everything. There are several ways to access this area! Good luck!

Travis
I just pulled the outside shower out and the tub drain area is right there.

I used the expanding foam from HD. That stuff supports a LOT of weight. Another thing that you could do, if you don't feel comfortable using expanding foam. You could just Jam in some packaging Styrofoam. I didn't think of that until after I sprayed the expanding stuff. Then I looked at it and said, "Oh MAN!! I hope I never have to work on that area".

Deb Mac, If you do use the expanding stuff, be sure to wear gloves. If you get that stuff on your skin, you have about 30 seconds to get it off with acetone. After that, live with it until it wears off.

[Deb Mac]

Having just returned from a wonderful 5-1/2 week trip I discovered that I do have a soft spot (soft enough to make me nervous!) at the rear of the tub just before you get to the rise that accommodates the converter.

So I think I will be pulling the converter out to try to access that particular spot. I'm going to install my tank flusher in the poor man's sealand too - I think I'll look at running the tubing through the tub surround next to the fan and down through the floor there, so I will be pulling that little screened box from under the P-trap again. While I'm there, I'll do some reinforcing of the floor around the drain. Mine is pretty good, but there is some flex that i may as well eliminate while I'm under there.

I think I'll place a lit flashlight face-down in the tub over the soft spot at the rear to give me a better idea of where it is, and the best angle to access it. I have lots of that stiff packing styrofoam at home, so I think I will try to use that rather than the expanding stuff. Easier to remove if I ever have to get at anything that it might block.

I am also in the beginning stages of my shower mod (thanks for the post SirDrake!). Already had the Oxygenics shower head, and have the new curtains ready to go in. But I want to address the floor issue first.

Haven't pulled the converter in this one yet. Anything I should be aware of before I dive in? Bill? You did it.

[Wavery]

Just be aware that after you remove the screws in the wall, it will take some effort to pull the converter straight out then to the left. There are a lot of stiff wires back there and it's a jungle of wire back there. Not a lot of room to work. Just take your time and carefully move the wires that are in your way. It will take some patience to get that box out enough to work in there. Just work it out easily.

Be sure to disconnect your negative battery cable (that will completely and safely delete any battery involvement) and be sure that the trailer isn't plugged in to 110V.

I ran my black tank washout through the outside shower and down through the floor. It was EZ. Just be sure to use some chafe protection for that plastic hose. I used a 4" piece of 3/4" PVC pipe.

[Deb Mac]

Thanks Wavery. I’ll look at that routing of the washout line. Sounds pretty straightforward.

I did get the screws out of the converter and pulled it part way out carefully. You aren’t kidding about the rat’s nest of wiring back there!! And yes… VERY stiff. I opted to wait for some input from you guys before I went any farther, so I put it back. BTW, 6 of the 8 spots where it screws into the wall were already broken. Old plastic! So I will look at repairing/reinforcing those spots on the frame of the box before I start messing around any more.

I’ll go back tomorrow morning and take another run at shifting that converter enough to work through that opening. And crazy glue the pieces of cracked plastic back into the box.
Almost want to create an access panel in the vinyl tub siding……. 🤔

[Wavery]

Once I got mine out past the wall paneling a little, I just pushed it to the left to have enough room to get in there. I was actually installing an automatic transfer switch in that rat's nest. It wasn't EZ but I got her done.

That when I used the expanding foam under the tub for reinforcement. I don't think that I could have gotten any styrofoam blocks in there but I thought about it. :cool: sorta :rolleyes::rolleyes:.... for a few minutes.:p

[Deb Mac]

����. I’ll give the converter removal a go tomorrow. Now that I know that it can actually be done (I was afraid to do much with it when I first pulled it out) I will bring a work lamp in there (dark in the hallway with no lights!) and some expanding foam (I have a can) and see what I can accomplish.

Thanks for the tips and encouragement. I’ll post an update tomorrow ����

[Deb Mac]

Can’t get the converter out of the way completely. A PO had cut the 30A power cord short and put a plug on it in order to use a regular free power cord instead of feeding it through the mouse hole. The remaining section of that cord is too short to allow me to move it far. Can get it out far enough to be able to shift enough of the remaining wiring that I can get my arm in a fair distance. Long skinny arms ;) .

Discovered that there is a sheet of styrofoam in there, but it isn’t long enough to completely bridge the channel over the grey tank waste pipe. So when you stand on that rear corner it sinks. Can’t get a picture since I can’t get my phone at the right angle through the wires. But I can feel where the gap is back there.

I can get good enough access to add more styrofoam but couldn’t correct that unsupported spot. I also can’t get a can of spray foam in behind the converter. I do have some tubing that I might be able to use to extend the tube on the can, and maybe that will work.

I think if I slide a couple of supporting pieces of styrofoam on edge along each side of the waste pipe (which I can do) I can slide a thin sheet of something over the gap and then fill the space between the tub and that little “table” with expanding foam without filling the channel around the waste pipe.

That’s tomorrow’s attempt. Now it’s time for supper and a couple of bandaids for my skinned knuckles and forearm.

[FlyboyTR]

After doing my initial repair as noted in this thread, over time and miles things shifted and my soft spot returned. Wavery's suggestion about using the expanding foam was a good suggestion. Except....

I had concerns about being able to remove the tub (if the need ever arose) because the expanding foam would have to be cut before the tub could be pulled. This was my solution...

I add a length of vinyl hose to the spray foam spout. I went in through the bottom/floor vent. I then inserted the hose into a lightweight garbage bag and then worked the bag into the area where I wanted to foam. Once satisfied with the bag placement, I then started spraying the foam. The bag expanded around the areas I needed. I did sort of pull the hose a bit and added more foam as needed until I was satisfied. After curing, I removed the excess bag.

I didn't remove any of the extra foam that had expanded beyond my intended target. Since the vent was still about 60% clear...I didn't worry about it. In hindsight, I wish I had used a smaller bag. BUT...things are solid and I have no worries about the foam being stuck to everything should service ever be needed.

Travis

[Wavery]

Great idea Travis. Probably 1 or even 2, 1-gallon Ziplock bags would do it.

[Deb Mac]

After doing my initial repair as noted in this thread, over time and miles things shifted and my soft spot returned. Wavery's suggestion about using the expanding foam was a good suggestion. Except....

I had concerns about being able to remove the tub (if the need ever arose) because the expanding foam would have to be cut before the tub could be pulled. This was my solution...

I add a length of vinyl hose to the spray foam spout. I went in through the bottom/floor vent. I then inserted the hose into a lightweight garbage bag and then worked the bag into the area where I wanted to foam. Once satisfied with the bag placement, I then started spraying the foam. The bag expanded around the areas I needed. I did sort of pull the hose a bit and added more foam as needed until I was satisfied. After curing, I removed the excess bag.

I didn't remove any of the extra foam that had expanded beyond my intended target. Since the vent was still about 60% clear...I didn't worry about it. In hindsight, I wish I had used a smaller bag. BUT...things are solid and I have no worries about the foam being stuck to everything should service ever be needed.

Travis

Excellent idea Travis. I was looking at that channel through the vent and thinking how easy it would be to just slide a tube in there and fill the gap from that direction. But how to block the foam from getting all over behind the converter.... Your idea covers all the bases!

I actually happen to have a couple of nice long bread bags that would probably do the job nicely. Figure I can double bag and that should ensure no leaks into unwanted spaces, or keep them to a minimum. And keep the foam from spewing into the space behind the converter. Should slide into that channel fairly easily and won't be too wide plus support the tub over the entire length of the channel.

The rest of the tub is actually pretty well supported... just that bit at the back corner where the existing styrofoam sheet isn't supported over the channel is really flexy. Will allow the tub and waste pipe to be dealt with should the time ever arise (of course hoping that never happens ;) ) Off to the trailer shortly. "News at 11"

[FlyboyTR]

Thanks. The bread bags should work. I used a low/medium expanding foam and went slow. If the outside shower panel was removed that would make things much easier, but I did mine strictly from underneath.

Wavery... The zip lock bags would work well also! Thanks!

[Deb Mac]

Great idea Travis. Probably 1 or even 2, 1-gallon Ziplock bags would do it.

Good thought Wavery…. I’m going to bring a couple of ziplocks as well. Might be easier to slide into place and a lot tougher than bread bags, especially the freezer bags…. I have many many ziplocks!

[Deb Mac]

Got a small sandwich sized freezer ziplock under the soft corner from the converter (vent) end. Couldn't get anything in there from the bottom. The supporting styrofoam is really pretty solid everywhere except that rear corner.
Slipped a length of vinyl tubing into the bag and zipped it mostly closed. Slid the baggie under the corner, attached the tubing to the nozzle of my foam and slowly filled the bag. Stopped when it was approaching the zip of the bag. Carefully backed the tube out of the bag (with my gloves on Wavery ;) ) and managed not to get foam on anything, including myself.
Foam continued to expand for a few minutes, creeping out of the opening in the zipper, but slowly and doesn't appear to have touched anything that it shouldn't.
I'll go back tomorrow after it has had some time to cure and test it. I imagine being contained in a plastic bag will slow the cure time down considerably. Likely won't bother trying to remove any of the excess. Let sleeping dogs lie!
Thanks to Travis for the bag idea, and Wavery for the ziplock tip.

[FlyboyTR]

Got a small sandwich sized freezer ziplock under the soft corner from the converter (vent) end. Couldn't get anything in there from the bottom. The supporting styrofoam is really pretty solid everywhere except that rear corner.
Slipped a length of vinyl tubing into the bag and zipped it mostly closed. Slid the baggie under the corner, attached the tubing to the nozzle of my foam and slowly filled the bag. Stopped when it was approaching the zip of the bag. Carefully backed the tube out of the bag (with my gloves on Wavery ;) ) and managed not to get foam on anything, including myself.
Foam continued to expand for a few minutes, creeping out of the opening in the zipper, but slowly and doesn't appear to have touched anything that it shouldn't.
I'll go back tomorrow after it has had some time to cure and test it. I imagine being contained in a plastic bag will slow the cure time down considerably. Likely won't bother trying to remove any of the excess. Let sleeping dogs lie!
Thanks to Travis for the bag idea, and Wavery for the ziplock tip.

My pleasure...! It sounds like you did a great job. Also, great job explaining what you did. We'll be looking for an update after it has cured.

Also...and FYI... Acetone will instantly dissolve the expanding foam WHILE IT IS WET. Every time I do something with expanding foam, I always have my acetone container close by. As soon as you're finished, remove the spout and you can pour it or squirt it through the delivery tube and it instantly dissolves the wet foam. Also pour/squirt some on the top of the can to clean the valve. Once it starts to set...the acetone will do nothing! So plan ahead and work fast!

[Deb Mac]

Well it didn't work. The stuff still in the bag didn't set. It all disintegrated back into liquid form. There was a nice big ball of cured foam outside of the bag. It had continued to expand slowly, but nothing supporting the floor. I suppose it is possible that with the "blob" sealing the edge of the ziplock, there was nowhere for the foam in the bag to expand to, and then just retracted. I will do an experiment with the remaining stuff in the can and see if it can work and what the optimal volume into a ziplock bag might be :)

So I carefully detached and pulled out "The Blob" (turns out it didn't adhere too robustly to the floor), attached to the ziplock, and went back to the styrofoam block approach. Managed to cut a wedge of the correct size that would both fit through the gap in the wiring that I was working through, and slide in behind the vent pipe and still be large enough to support the corner. It needed to actually support the back wall and flat floor of the tub at that spot.

Floor is now nice and solid. I imagine with time and motion it may shift, but at least I know how to get at it now and exactly where I need to work. If at some point I can get the converter to shift out of the way so I'm not working through an arm sized gap between the converter and the wall, I might be able to do a more permanent fix. But until that time, I will get by fine with what's there now.

[Wavery]

I think that you would have to leave the bag open. It needs air to expand and cure. This stuff needs moisture and oxygen to expand. Normally the moisture in the air is enough but in this case, wetting the inside of the bag may be necessary.

[Deb Mac]

You’re probably right about the air. I’ll take what’s left in the can and see what the expansion volume turns out to be in an open bag. Maybe next time tuck a long bag under that corner with a much smaller volume of foam injected.

[FlyboyTR]

Well it didn't work. The stuff still in the bag didn't set. It all disintegrated back into liquid form. There was a nice big ball of cured foam outside of the bag. It had continued to expand slowly, but nothing supporting the floor. I suppose it is possible that with the "blob" sealing the edge of the ziplock, there was nowhere for the foam in the bag to expand to, and then just retracted. I will do an experiment with the remaining stuff in the can and see if it can work and what the optimal volume into a ziplock bag might be :)

So I carefully detached and pulled out "The Blob" (turns out it didn't adhere too robustly to the floor), attached to the ziplock, and went back to the styrofoam block approach. Managed to cut a wedge of the correct size that would both fit through the gap in the wiring that I was working through, and slide in behind the vent pipe and still be large enough to support the corner. It needed to actually support the back wall and flat floor of the tub at that spot.

Floor is now nice and solid. I imagine with time and motion it may shift, but at least I know how to get at it now and exactly where I need to work. If at some point I can get the converter to shift out of the way so I'm not working through an arm sized gap between the converter and the wall, I might be able to do a more permanent fix. But until that time, I will get by fine with what's there now.

Deb,
I am so sorry that it didn't work out for you. The day I did ours we were in our typical 95% humidity and I used a bag that I didn't try to close/seal...so it was open. I guess air was able to make it's way through the bag. Maybe that is why mine worked without issue. Could be that a larger bag is the answer. Glad you were able to get some support under the tub.

[Deb Mac]

Do you recall what brand of foam you used? There may be some differences in chemistry that allowed yours to work in that somewhat enclosed setting.
Plus it is dry as a bone up here. Likely a very poor combination of conditions for foam in a bag.

[FlyboyTR]

Do you recall what brand of foam you used? There may be some differences in chemistry that allowed yours to work in that somewhat enclosed setting.
Plus it is dry as a bone up here. Likely a very poor combination of conditions for foam in a bag.

Don't remember exactly which foam I used. It came from Home Depot. I would say try it with a large (kitchen/bathroom) type. So...you're not trying to fill the bag, but applying the foam where you need it but just inside the bag. If things are really dry, I would say to wet the bag first. The larger bag will allow air space around the foam. So maybe with the water and the air space, it may make a difference.

[Deb Mac]

Don't remember exactly which foam I used. It came from Home Depot. I would say try it with a large (kitchen/bathroom) type. So...you're not trying to fill the bag, but applying the foam where you need it but just inside the bag. If things are really dry, I would say to wet the bag first. The larger bag will allow air space around the foam. So maybe with the water and the air space, it may make a difference.

I'll give that try when I need to get at it again. Or if I get a chance before the cooler weather hits us. Labour day coming... up here we could see snow any time after that! But I don't think that's likely this year!