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

[Minerrick]

....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?

[Minerrick]

JoeH wrote:

dpglifestyle wrote:
As far as the bulge from the tank you can run a steel strap from frame rail to frame rail under the tank. Install with an empty tank, pull tight and screw to the frame. A lot of units come this way.

I would put a strip of old inner tube rubber or similar material to cushion the plastic tank from the steel.

Nah, we live in a home in Truckee, so we have no intentions of trying to live a winter in it (Brrrrrrr). We use it typically for early and late fall camping, and oftentimes we get caught in snowstorms and cold weather, so we just want to try to keep it a bit warmer.

[JoeH]

dpglifestyle wrote:
As far as the bulge from the tank you can run a steel strap from frame rail to frame rail under the tank. Install with an empty tank, pull tight and screw to the frame. A lot of units come this way.

I would put a strip of old inner tube rubber or similar material to cushion the plastic tank from the steel.

[Blazing_Zippers]

minerick, a dealer installed three steel angle beams from one frame rail to the other to stop tank sag. They were screwed in the frame and were under the coreplast. This was on warrantee. I can't comment on the repair, because 75 miles later an axle locked up and we crashed the entire rig. It was an Arctic Fox 25R brand new. YeeHaw!
As a former resident of Truckee, I know how cold it gets. Are you trying to insulate the camper for winter usage or do you intend to tow it after the mods? If you're intending to park it for winter, you might consider the moisture element also. Propane heaters and stoves put out lots of dampness.

[campigloo]

When I got my panels they recommended well nuts. I couldn’t find any locally. I used hollow wall anchors and they’ve worked good. The sheeting on mine is 3/8 chip board. Call the manufacturer and they will probably tell you what’s up there. Three years and ~40k miles and there still very solid.

[Minerrick]

I was thinking the same thing.... thanks for the tip.

[agesilaus]

dpglifestyle wrote:
As far as the bulge from the tank you can run a steel strap from frame rail to frame rail under the tank. Install with an empty tank, pull tight and screw to the frame. A lot of units come this way.

Exactly what I was thinking, use plumbers strapping aka hanger strap

Amazon

Get it at any hardware store.

[dpglifestyle]

As far as the bulge from the tank you can run a steel strap from frame rail to frame rail under the tank. Install with an empty tank, pull tight and screw to the frame. A lot of units come this way.

[BackOfThePack]

Skirting is a better choice. Heavy-vinyl (snap). Blocking air movement is that which “insulates”.

Otherwise, avoiding moisture collection (accelerating rust & rot) is a genuine problem to solve when installing underfloor insulation

[Minerrick]

So, after looking at this project for the last half hour, due to the sagging tank bottoms not allowing me to put any thickness of rigid insulation on them, I think I am going to furr out the bottom rails of the frame I beams with 1.5" pressure treated 2x4, ripped down to 1.5". I haven't seen anyone do this, but I think it will work.... it will make the bottom of the frame 1.5" lower, but it will allow me to put some rigid 1" insulation under the tanks and not have a huge bulge hanging down. I can use some spare Coroplast to wrap the edges of the 2x4 exposed to any potential water. It will simplify screwing the coroplast by being able to screw it in to the wood 2x4 rather than having to try to line up the old holes drilled into the steel. I guess the drawback is that the wood screws could back out over time. Thoughts? The reason I want to get away from fiberglass insulation on the bottom of the tank, was the old fiberglass I pulled out was re-arranged into nice little mice nests, and it was disgusting, not to mention, not very insulative.

[C_Schomer]

The bottom of mine uses FG so it conforms to the space. It makes the coroplast bulge a little, but who cares? The roof trusses are usually on 16" centers, so it's easy to find one at a vent, ac etc. and measure from there. I'd use a small drill bit to find the exact location. I'd also try a stud detector on the roof. Flooring is usually 5/8 plywood but I wouldn't count on anything in a slide. Craig

[Minerrick]

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.

[Minerrick]

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.

[valhalla360]

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.

[Lwiddis]

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.