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Mike_Ehrmantrau's avatar
Mike_Ehrmantrau
Explorer
Oct 14, 2015

Water Damaged Wall in Class C

I purchased a 1997/8 Class C Four Winds Dutchman earlier this year. It was a little bit of a fixer upper but it seemed to be in good mechanical shape.

After I purchased it and did some climbing on the roof, I discovered that the RV had a leak at one point all along the driver's side. The ceiling and roof seem to be sturdy but the wall in the bathroom had peeling wallpaper.

My plan had been to add a rising grab bar in the bathroom for my father who has mobility issues. I figured I would need to a couple of layers of plywood to the existing plywood wall once I peeled away the bad wallpaper.

Once I pulled the paper away and attempted to fix the plywood, I discovered there is not much more than luann between me and the foam insulation. Also, I am not sure if the metal bar in the wall is the spine that holds the RV together.

Attached below are pictures I took tonight after pulling down some of the plywood/luann.

If I wanted to attach a liftable grab bar to the exterior wall, what could I attach it to?

Should I layer thin layers of plywood against the wall to rebuild the interior?

Could I attach the plywood to the metal bar in the picture via screw or rivet?

Any thoughts or feedback would be appreciated.






The metal bar is just to the left of the gap. It looks like the foam insulation was miscut 18 years ago and the gap was left behind.

  • shepstone's avatar
    shepstone
    Explorer
    Oct 14, 2015
    Pretty nasty stuff there. You will have to find out if there are studs of any kind in the wall and rebuild from there. I cant tell if the metal piece is a stud or not , you will have to remove some more of the luan to find out for sure. Does the rot go all the way to the outside wall?
  • Mike_Ehrmantrau's avatar
    Mike_Ehrmantrau
    Explorer
    Oct 14, 2015
    shepstone wrote:
    Pretty nasty stuff there. You will have to find out if there are studs of any kind in the wall and rebuild from there. I cant tell if the metal piece is a stud or not , you will have to remove some more of the luan to find out for sure. Does the rot go all the way to the outside wall?


    Hard to tell. It does appear to be a stud. Would you suggest I peel back more and take more pictures? I was planning to use Abatron's Liquid Wood to harden dry rotten stuff. I have used it in the home before with good success.
  • westend's avatar
    westend
    Explorer
    Oct 14, 2015
    Pull that nasty luan off there and add some more framing into the wall for the grab bars would be my suggestion. Be sure to fill all the cavities with insulation before a new wall panel is installed, it will make everything tighter and more comfortable.
  • Mike_Ehrmantrau's avatar
    Mike_Ehrmantrau
    Explorer
    Oct 15, 2015
    westend wrote:
    Pull that nasty luan off there and add some more framing into the wall for the grab bars would be my suggestion. Be sure to fill all the cavities with insulation before a new wall panel is installed, it will make everything tighter and more comfortable.


    Should I sister the wood to the metal frame member?
  • westend's avatar
    westend
    Explorer
    Oct 15, 2015
    Mike_Ehrmantraut wrote:
    westend wrote:
    Pull that nasty luan off there and add some more framing into the wall for the grab bars would be my suggestion. Be sure to fill all the cavities with insulation before a new wall panel is installed, it will make everything tighter and more comfortable.


    Should I sister the wood to the metal frame member?
    That's certainly one way to do it. If possible, I'd fasten a 2 x 4 across the cavity, drilling from the opposite edge of the two studs forming an "H" in the cavity. Positioning a cross member across the cavity will strengthen the wall considerably.
  • Mike_Ehrmantrau's avatar
    Mike_Ehrmantrau
    Explorer
    Oct 16, 2015
    westend wrote:
    Mike_Ehrmantraut wrote:
    westend wrote:
    Pull that nasty luan off there and add some more framing into the wall for the grab bars would be my suggestion. Be sure to fill all the cavities with insulation before a new wall panel is installed, it will make everything tighter and more comfortable.


    Should I sister the wood to the metal frame member?
    That's certainly one way to do it. If possible, I'd fasten a 2 x 4 across the cavity, drilling from the opposite edge of the two studs forming an "H" in the cavity. Positioning a cross member across the cavity will strengthen the wall considerably.


    I pulled down as much of the luan as possible. It feels like the glue that the manufacturer used to glue the luan to the foam insulation is pretty strong.

    I was able to expose the supports in the wall and I am a little baffled. The supports appear to be rectangular aluminum tubing from the ceiling to about two feet from the floor. Then square tubing is attached above and below the rectangular tube. With additional tubing meeting it in the middle, but they do not appear to touch.

    I would love to attach a 1X2 or 2X3 horizontally between two vertical "beams" but the other beam would be behind shower wall. I am wondering if I put additional vertical wood in the wall if this would work.





  • shepstone's avatar
    shepstone
    Explorer
    Oct 18, 2015
    Here is my suggestion. & I am familiar with residential and commercial construction but not so much with rv's.
    How strong is the remaining luan at the edges of the tub and oposite wall? Is it strong enough to glue a sheet of plywood to it with a v notched trowel at 100% coverage? Then if needed, screw into the steel studs that you can find getting the screw heads down to just below the surface( mark the studs out first). The additional smaller "tubing" could be conduit for electrical, so avoid screwing into that. One continuous sheet of paint grade ply would be best if you can get it into there, it wouldnt need to be too tight , leave a gap of about 1/4" all round , test fit first .You can use a spray foam to fill the gaps if needed and cut it to the surface when it dries, (use masking tape around all the existing edges) then fill the screw holes use molding around the edges and sand and paint with bathroom / kithchen paint . Remember to caulk at the tub surround and at the floor.
  • Mike_Ehrmantrau's avatar
    Mike_Ehrmantrau
    Explorer
    Oct 27, 2015
    shepstone wrote:
    Here is my suggestion. & I am familiar with residential and commercial construction but not so much with rv's.
    How strong is the remaining luan at the edges of the tub and oposite wall? Is it strong enough to glue a sheet of plywood to it with a v notched trowel at 100% coverage? Then if needed, screw into the steel studs that you can find getting the screw heads down to just below the surface( mark the studs out first). The additional smaller "tubing" could be conduit for electrical, so avoid screwing into that. One continuous sheet of paint grade ply would be best if you can get it into there, it wouldnt need to be too tight , leave a gap of about 1/4" all round , test fit first .You can use a spray foam to fill the gaps if needed and cut it to the surface when it dries, (use masking tape around all the existing edges) then fill the screw holes use molding around the edges and sand and paint with bathroom / kithchen paint . Remember to caulk at the tub surround and at the floor.


    Thanks for the suggestions.

    I am hoping the square tubing is not electrical, as the manufacturer put a dozen or so brads into it to hold up the original luan.

    As I pulled away the dry rotted luan, I see that the square tubing is spot welded to the vertical metal beam. I am still not sure what the metal is made of but the vertical beam is much thinner than the horizontal running square tubing.
  • DrewE's avatar
    DrewE
    Explorer II
    Oct 27, 2015
    Mike_Ehrmantraut wrote:

    I am hoping the square tubing is not electrical, as the manufacturer put a dozen or so brads into it to hold up the original luan.

    As I pulled away the dry rotted luan, I see that the square tubing is spot welded to the vertical metal beam. I am still not sure what the metal is made of but the vertical beam is much thinner than the horizontal running square tubing.


    If the tubing (either horizontal or vertical) is attractive to a magnet, it's steel. If it isn't, it's aluminum. Those are the only two options for metal that I've heard of for RV wall frame construction. I think the aluminum is more popular, and brads would be more easily driven into it than into steel, so that would be my first guess. It's very doubtful that they would use a mixture of the two in a wall frame, and certain that they couldn't successfully weld the two together.
  • Mike_Ehrmantrau's avatar
    Mike_Ehrmantrau
    Explorer
    Oct 27, 2015
    DrewE wrote:
    Mike_Ehrmantraut wrote:

    I am hoping the square tubing is not electrical, as the manufacturer put a dozen or so brads into it to hold up the original luan.

    As I pulled away the dry rotted luan, I see that the square tubing is spot welded to the vertical metal beam. I am still not sure what the metal is made of but the vertical beam is much thinner than the horizontal running square tubing.


    If the tubing (either horizontal or vertical) is attractive to a magnet, it's steel. If it isn't, it's aluminum. Those are the only two options for metal that I've heard of for RV wall frame construction. I think the aluminum is more popular, and brads would be more easily driven into it than into steel, so that would be my first guess. It's very doubtful that they would use a mixture of the two in a wall frame, and certain that they couldn't successfully weld the two together.


    Is it possible it is galvanized? Considering there was water damage, I did not see any rust.

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