Bowing/Buldging Walls

[RamblinAnne]

I'm noticing some bowing of the walls inside my Bigfoot. I spent Dec-Mar living in the camper while it was off the truck and never had this issue (though I did notice some gaps where the floor meets the walls). Now the camper is primarily in the bed of my truck and I rarely put the jacks down. Since it's been in the truck, I notice this issue of the bowing walls. (But the gap issue has gone away). I did a search on the issue and it said it could be delamination due to moisture getting in. It's true that one wall is near a window and another is in the bathroom. But I am super diligent about checking for leaks on a very regular basis and I don't think I have any water coming in. What is the problem and how do I fix this? Is it just normal compression of being in the truck bed?

One thought, particularly in regard to the bathroom wall, is that I removed the sink, installed new flooring, and reinstalled the sink in the same place. I'm wondering if the small shift in flooring could be pushing up on the sink (the more noticeable buldge). But that doesn't explain the spacing by the dinette.. at least I don't think.. unless it's all kind of shifting due to this sink placement.

Any input would be greatly appreciated!

[RamblinAnne]

So I'm currently at an RV repair shop. I decided to at least take it in for an estimate since I really don't have much time to do the work myself. We're waiting on a call back from Bigfoot since the repair shop guys are a bit perplexed by my issue and whether or not it's an actual problem or simply just a cosmetic thing. We raised the camper off the truck and as I suspected, the issue "fixed" itself. They agreed that there is absolutely no evidence of any water damage and said this is not a delamination issue. I'll continue to update as I learn more about what is causing this, if it's a real problem, and what the solution is. Thanks for tuning in on this week's ramblin Anne's rants. 😃

[3_tons]

I’m not at all familiar with BF, and don’t know if this is a contribuiting issue but would like to point out the water weight in the fresh water tank can be a substantial factor when camper is unloaded and unsupported from the truck bed...tanks should always be emptied before unloading...

3 tons

[bcbigfoot]

RamblinAnne if you could check with the camper on the truck for several days, look along side of the camper from the rear drivers side jack and look forward towards the truck, just above the electrical cord door or external shower door, is there a long arching bulge about 2 feet long. You can use a 2x4 or straight edge to help see it.

My camper had a bulge and delamination in this area so I removed the external shower door, city water fill door frame so on and injected a sikaflex polyurethane adhesive and also laminated a 1/2" plywood on the inside, on the outside I fabricated aluminum plates that went around the door frames, then ran 1/4 bolts trough to sandwich everything back together. It really didn't work I still had some bulging, I came to realize this was not the root cause of the issue and the delamination was just a symptom of a different issue. Once I replaced the cut out section that external bulge went away. I also laminated 1/2 inch plywood along an internal basement wall ( if you can call 1/4" luan, stapled to some 3/4" x 1 1/2" a wall), it's the wall between the grey tank and the fibreglass basement (hope that makes sense). This new plywood acts as truss between the floor you walk on and the basement floor as the floor you walk on has also been mostly cut away to make room for the black tank (upper tank)and plumbing. Your 10.6' my be somewhat different than my 9.6'.

I don't believe Bigfoots suffer from the same issues of external basement walls crushing under the weight of the camper as some Northernlites had issues with, I believe member coveredwagon had a issue with this at one time. The Bigfoot external basement walls are fiberglass then 1/2" plywood, expanded polystyrene, 1/4 luan, and then a light coating of fiberglass chop.

I had the dinette separation like yours with the camper on the truck, the small wall from the tub to external wall my camper doesn't have. Two years after doing the work I still get 3/16 inch separation even after installing the plywood inspection plate however it is based on hot and cold expansion. Overnight with freezing temps and heated inside the gap closes up tight, then during the day if sun shines on that wall it will open up again a little, before it would always remain a big gap and continue to get bigger the longer it sat on the truck.

[RamblinAnne]

More pics of the separation...

[TxGearhead]

bcbigfoot...thanks for the explanation of the cardboard model. The rear wings would seem to add to leverage being they are unsupported. I'm thinking that transition to the wings would be a high stress area. At least it's not a drop down floor and add even more leverage. I've never removed my inspection cover. Might do that this fall.

[RamblinAnne]

Wow. Awesome responses guys. I seriously appreciate all this info. Okay! So! I climbed up on the roof to inspect skylight- all good. I ripped the sink out from the wall (the issue I suspected was causing he buldge in the first place) and inspected back there. No signs of any leaks, rotting, or water damage whatsoever. I took off the panel behind the dinette seat back- again, no signs of any water damage. This is good news! But! I do see where the "perpendicular" walls are separating from the "parallel" walls. As was said above, because these are interior walls, I no longer think this is an issue of delamination. I think this is probably a two part problem of the newly installed floor boards shifting/crunching up on the walls causing them to buckle. And like bc bigfoot said, the issue of the cut out/inspection plate not being properly supported.

Since I believe I am about 99% sure of this diagnosis- I may opt to do the work myself as opposed to taking it into the shop. I may call and try to get an estimate just to weigh my options but don't feel like driving 2 hours and being Without my home for a few days just to have them quote me something outrageous.. It sounds like I have a pretty big job on my hands but I'm up for the challenge. Bc bigfoot- I may have more questions for you along the way as I prepare to (finally) get this issue taken care of.

Thank you everyone!!

[bcbigfoot]

TxGearhead wrote:
"This my sound a little strange but I highly recommend you make a cardboard model of your camper rear wings of the camper and everything, just use duck tape or hot glue gun to hold it all together, cut out the sections of the bottom that Bigfoot cut out. This will show you how flimsy the rear wings and overhang are, then with glue or tape reinstall the bottom that was cut out. You will quickly understand what's going on structurally with your camper."
"^^I'm not following the above. What do you do with the cardboard after you make the model? Did you cut out plywood to replace the plastic inspection cover, or cover the entire bottom with plywood?

"

The model will quickly demonstrate the structural issue with the camper, this will give RamblinAnne a understanding of the problem and a possible course of action. Dropping the camper off at a RV dealer and getting them to fix it is just a invitation to be taken advantage of. Knowledge is the only defense against RV dealer abuse.

"Texagearhead Quote: Did you cut out plywood to replace the plastic inspection cover, or cover the entire bottom with plywood?"

I did both but it was likely overkill, I have long term plans for the camper (10+ years) and wished to error on the side of caution. It is very difficult to explain but, I framed the opening of the rear overhang with approx. 1"x2" then cut out a tight fitting 5/8" plywood plug, screwed that up into the framed 1"x2". This was done with the camper on the jacks as the dimensions of this opening can change up to 3/8" when sitting on the camper after a few weeks. The elongation and movement of that opening is what's trying to be prevented.

After this I placed 2 cut out sheets of 5/8 marine grade plywood (edges treated with West System resin) over the entire bottom of the camper and screwed up into the basement structure of the camper similar to plastic inspection cover. I used a rope of butyl caulking between plywood and camper structure then sealed the gap with Sekaflex urethane sealant. It will take some work to get in again but see no reason to for many years, Northernlites don't have inspection plates.

On my camper I added a Honda generator and a rear platform with electric step, this adds a lot of leverage to the overhang of the camper and felt the extra sheets of plywood was insurance.

Also the external side wall on my camper above the overhang on the side of the cut out would bulge out when the camper was on the truck and then disappear when on the camper jacks, that bulging has been eliminated.

[TxGearhead]

"This my sound a little strange but I highly recommend you make a cardboard model of your camper rear wings of the camper and everything, just use duck tape or hot glue gun to hold it all together, cut out the sections of the bottom that Bigfoot cut out. This will show you how flimsy the rear wings and overhang are, then with glue or tape reinstall the bottom that was cut out. You will quickly understand what's going on structurally with your camper."
^^I'm not following the above. What do you do with the cardboard after you make the model? Did you cut out plywood to replace the plastic inspection cover, or cover the entire bottom with plywood?

[bcbigfoot]

RamblinAnne Quote: "Still curious if any Bigfoot or northern lite owners have ever actually had this issue, fixed it and what your solution was."

I have had this issue on my 2005 Bigfoot 9.6e 2500, I believe it's basically the same camper as yours except yours is dry bath with a longer rear overhang. I posted approx. a year ago in your thread about your warping, cracking plastic bottom inspection plate, That warping inspection plate is your issue. Bigfoot cut out large parts of it's structure and then installed a flimsy plastic cover. When the camper is on the jack's that section of camper, what used to be the bottom of the camper, goes under tension forces, then when you put the camper on your truck it goes to compression forces, and you get a pucker or warping of your thin plastic inspection plate. I did a great deal to fix this but bottom line is you need to replace that section of floor that bigfoot removed and make it a structure again. Simply put I removed the flimsy plastic and installed 5/8" plywood across the bottom of the camper.

This my sound a little strange but I highly recommend you make a cardboard model of your camper rear wings of the camper and everything, just use duck tape or hot glue gun to hold it all together, cut out the sections of the bottom that Bigfoot cut out. This will show you how flimsy the rear wings and overhang are, then with glue or tape reinstall the bottom that was cut out. You will quickly understand what's going on structurally with your camper.

Arm yourself with a little knowledge, and your cardboard model of your camper and the dealers will find it difficult to take advantage of you. Find someone that will listen to you, if they don't move on.

[covered_wagon]

I have a similarly built northern lite camper that delaminated and bulged the fiberglass shell after winter use. It occured where the cabover attaches to the main body. I repaired and reinforced before it got cracked and more difficult to repair.

Basically laminated the inside wall with prefinished oak flooring, 3/4" and thru bolted an aluminum plate to the outside. Thereby squeazing the bulge and wall back together. This plate acts also as a strut across the area of required compressive strength and keeps it from bulging from the pressure from the weight.

May be off topic a bit but gives an idea of some other ways to deal with this issue.

[54suds]

bigfoot knows of this problem Ive had one sent back to BC fixed and returned at company expense. another I brought back several weeks before to went bankrupt then ,they only did cosmetic repair that fell apart in a couple of weeks use. and ive had to fix 3 more with this .

[Z-Peller]

RamblinAnne

First of all I would look for a plumbing leak behind that fiberglass shower stall. Maybe the shower tap water lines? Those lines are always pressurized to the shower taps, even if you don't use them much. Both of your bulging/ separating issues are walls the shower stall backs onto which makes me suspicious. Did you have the sink out to do the flooring?...or maybe the sink plumbing got jostled during the process and is now leaking?....those walls you are showing in your pics are just Luan over light spruce framing members. The wall between the settee and shower might have some plywood in it.

I have owned 2 Bigfoot campers, and a Bigfoot trailer, and have never had any structural issues.
Yes I know, never say never, but I would start looking at the more simple things first.

[HMS_Beagle]

Is the wall in question and exterior wall or an interior (partition) wall?

On a Bigfoot, the top and bottom halves are molded from fiberglass, about 1/8" thick. This is too thin to be stiff enough to build a camper out of. They then laminate foam to the inside of the fiberglass using a contact cement, with solid wood reinforcing in various places that will support interior and roof items. Then 1/8" luan is laminated on the inside of that, again with contact cement. The foam used to be extruded polystyrene but in later years it is expanded polystyrene "bead board". The resulting sandwich makes the panels stiff enough to survive as a camper. This is only on the exterior walls. The interior walls are stick built like most campers, light weight solid wood framing covered with 1/8" luan, usually stapled and sometimes also glued in place.

If an exterior wall has the panelling buckling, it is delaminated from the foam and is - or can turn into - a structural issue. If it is an interior wall coming loose from the lightweight framing, it could be warping from moisture, or stress from some of the causes postulated above, but it is not likely to be or become a structural problem. Figure out whats pushing or warping it, then staple it back in place.

[notsobigjoe]

I wonder if the the floor is rotted. It hangs normally when your on jacks but crushes up when you put weight on it. JM2C