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Minerrick's avatar
Minerrick
Explorer
Sep 07, 2020

I'm installing rigid insulation on the underbody.....

....of my 2002 Arctic Fox 24.5N FW and I have some questions: When I took the old coroplast off, the bottom of the holding tanks were sagging downward a little, thus causing the coroplast to sag downward. I plan on putting 1" rigid insulation between the new sheet of coroplast and the tank, but it is make a bigger downward bulge under the tank. Should I screw on a little piece of 2x4 around the downward edge perimeter of the frame (around the tank) in order to make it so when I put the coroplast up, everything is flush without a big sag in the center of the coroplast? In other words, I would be extending downward by 1.5" the edge of the steel frame. Sure I would decrease the (body) ground clearance by 1.5", but I don't think that will make much of a difference.

Question #2: I have a single slide out and I want to insulate in that outside frame space too. But I don't want to screw anything into the mechanism that extends the slide out(for obvious reasons), so could I just press some rigid insulation up next to the bottom side of the floorboards and then use wood screws to screw through the insulation, into the plywood floor above? Does anyone have any idea how thick the floorboard plywood is? I don't want the screw tips tearing up the bottom of the slide as it moves in and out.

#3. Not insulation related... but why not? I will be installing a solar panel on the roof. How are the roofs of these things designed? Is the roof a solid piece of plywood, or is it just a frame with studs and you have to find a specific location to penetrate the roof for attaching the solar panel and wire penetrations? I am thinking of getting rid of the crank up TV antenna we never use and using that penetration through the roof as the location of the solar panel wire roof penetration.

Any suggestions?

17 Replies

  • agesilaus wrote:
    Fabric based? What are you using? We assume foam board insulation which has no fabric in it so far as I know. It is glued with 'liquid nail' type cement they have some designed for foam boards. You'll find that at your big box hardware store.

    As for solar panels people are using 3M double sided tape, not the stuff hanging on the shelf at Lowes tho.


    So, the "insulation" on the underside of the trailer is some sort of black fabric on the underside, with (I assume) a thin layer of fiberglass on the side facing the living space. Max 1/4" fiberglass insulation.
  • valhalla360 wrote:
    I don't think you will be able to insulate the bottom of the slide as it has to go up over the interior floor when it's pulled in.

    Or maybe I'm not understanding what you are proposing.



    I am talking about insulating the part of the floor that is under the slide when the slide is slid in. So it's the part of the camper that DOESN'T slide when the slide slides out. When we are boondocking, that floor area under the kitchen is cold as hell and I am thinking insulation can help.
  • I don't think you will be able to insulate the bottom of the slide as it has to go up over the interior floor when it's pulled in.

    Or maybe I'm not understanding what you are proposing.
  • If you have a rubber roof attach the solar panels with screws. If you have a fiberglass roof use 3M tape, as age said not the stuff at Lowe’s.
  • Fabric based? What are you using? We assume foam board insulation which has no fabric in it so far as I know. It is glued with 'liquid nail' type cement they have some designed for foam boards. You'll find that at your big box hardware store.

    As for solar panels people are using 3M double sided tape, not the stuff hanging on the shelf at Lowes tho.
  • 2. What kind of glue would you recommend to attaching to the fabric-based insulation already there under the slide?

    3. How do I find the roof trusses?
  • jdc1's avatar
    jdc1
    Explorer II
    1. Do not let anything rub the bottoms or sides of your tanks. They will wear through.
    2. Why not glue the panels under the slide-out area?
    3. Remove the antenna, leave the mount. You find a better place to run the solar wiring (unobtrusive) like down a vent pipe or through one of these:
    https://www.amazon.com/Waterproof-Restmo-Weather-Resistant-Housing/dp/B07WL7D9V6/ref=sr_1_2?dchild=1&keywords=rv+roof+solar+parts&qid=1599500163&sr=8-2

    Oh....and yes. You should locate the roof trusses to screw in the windward mounting brackets.

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