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SettingOutSoon's avatar
Feb 10, 2014

Advice on tear-down/rebuild?

I want a 5th Wheel/TH about 38' long, and I'm debating whether to build from scratch (on a drop deck trailer) or buy a cheap, used 5th Wheel/TH and tear it down to the "foundation" and rebuild. (I've given up the idea of moving prefab walls, and I want a structure that will support a rooftop deck.) Any advice?

What chassis would you recommend? Three axles much better than two? Newer Thor or Forest River better than older Nu Wa, Newmar or Travel Supreme? What should I be most focused on?
  • Thanks for posting back, that all makes sense to me.

    Most don't do what you're asking for, but I do see them. The owner/creators seem pretty happy with the results after it's all done. The one's I've seen almost always started out with some form of a cargo trailer, and went from there.

    Good luck on your project.
  • QUOTE: "I personally would stay away from SIP's for the construction of a TH or any other TT for that matter because of the dynamic forces that trailers generate by being towed (wind loading, weight shifting, braking, etc). To me you'd constantly be chasing leaks (water and air) and all the other problems that trailers incure due to all the bending and twisting they encounter. In engineering terms it's called 'rotation'."
    ---------

    I don't have the expertise to exactly pinpoint why this sounds right, but it does. Maybe it's just the idea of dragging ANY cracker box house down the highway at 70 MPH and then down dirt roads for very long!

    My problem is that I can get a wood-framed or SIP panel house build pretty cheaply, and even if my guys have a steep learning curve attaching it to the frame and doing RV plumbing, it's doable. To do what you did--with steel fabrication, etc.--I think I'd have to get a factory to do it for me, at great cost.

    Any idea how I could find out which older model 5th Wheels and THs *were* framed strongly? Are there some out there where we could gut and reconfigure?
  • John&Joey wrote:
    Do you mind me asking what your ultimate goal is? Is it to save money, or to get a unique rig to fit a specific event. Just wondering.


    Don't mind at all, maybe you have some good advice. My last child goes to college this year. I'm selling the big house (I'm single and 52), and want to (a) live mortgage-free and (b) enjoy life from my rooftop deck, moving my home/office between the mountains (grandkids), Washington DC (work) and the beach. That's my idea of a good life for an old guy who doesn't have to live just for his kids anymore. Not really planning to hit the highways and see the USA anytime soon.

    There are two reasons I want to build. First, I've looked at hundreds of RVs, and I just can't see a way to adapt them to what I want. If I could afford a class A toy hauler and pull a Smart Car into the garage, I might. Otherwise, I need a towable that is strong enough for a rooftop deck. I'd also like to open up the back (TH ramp) or the side (fold down patio), so that I don't feel cooped up. I could buy a cheap toy hauler and renovate it to my needs, but they're built so flimsy! What is there to work with??

    Second... If I could build anything, I'd love to put a more or less conventionally built modular unit on a trailer, that I could *dock* on my land as part of my permanent homestead. That's looking more and more like a luxury I can't afford right now, but if you're interested in what a Texas architect built like that, here's a very cool example:



    Source: http://andrewhinman.com/images/portfolio/02-locomotive/5.jpg
  • Do you mind me asking what your ultimate goal is? Is it to save money, or to get a unique rig to fit a specific event. Just wondering.
  • SettingOutSoon wrote:
    BoonHauler, I see you framed your rig with tube steel. That would clearly support a rooftop deck. Do you have an opinion about building with SIP panels? How much might that save in weight and how smart would it be? I have very accomplished tradesmen in my family, but none have built on a trailer (my son has *built* trailers, but not houses ON them...)


    Setting Out Soon:

    I personally would stay away from SIP's for the construction of a TH or any other TT for that matter because of the dynamic forces that trailers generate by being towed (wind loading, weight shifting, braking, etc). To me you'd constantly be chasing leaks (water and air) and all the other problems that trailers incure due to all the bending and twisting they encounter. In engineering terms it's called 'rotation'.

    I've been chatting with a few others on this board that are very competent and now that I've built a trailer from the ground up I'd do a lot of things differently.

    The first would be to lighten the guage of the steel framing materials that I used. I'd have to think I'd be able to lose about 30% of the frame weight by doing so.

    One of the requirements of my project was a full on walk on roof and I have that, it's bulletproof and can easily handle the weight of many people. The framing itself is bulletproof.

    If you've taken the time to read through both the threads that are on SBR you'll have a good idea of what the project is all about. I've come to the conclusion that most, if not all, factory built TH/TT are junk and that's why I decided to build mine from the ground up. This way I know what I'm getting, it's not cheap and it's not easy but it will be well worth it once the project is finished.

    I'll be retiring soon and will be going fulltime and I'll feel much better knowing that I've taken the time to do it right.

    If you like to discuss things further fell free to send an email. My address is on the front page at SBR.

    Good luck and Happy RVing ...:)
  • BoonHauler, I see you framed your rig with tube steel. That would clearly support a rooftop deck. Do you have an opinion about building with SIP panels? How much might that save in weight and how smart would it be? I have very accomplished tradesmen in my family, but none have built on a trailer (my son has *built* trailers, but not houses ON them...)
  • Ken and Kathy, thanks very much for the link!

    BoonHauler, what are you trying to do, break my spirit? I've never felt so under qualified and in over my head in my life. Very impressive!!
  • SettingOutSoon wrote:
    I want a 5th Wheel/TH about 38' long, and I'm debating whether to build from scratch (on a drop deck trailer) or buy a cheap, used 5th Wheel/TH and tear it down to the "foundation" and rebuild. (I've given up the idea of moving prefab walls, and I want a structure that will support a rooftop deck.) Any advice?

    What chassis would you recommend? Three axles much better than two? Newer Thor or Forest River better than older Nu Wa, Newmar or Travel Supreme? What should I be most focused on?


    Checkout my build thread BoonHauler Project
    Trust me, it's a lot of work!

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