Re-insulating, avoiding dust

[Joannad]

This is a follow up on my first thread on rot (https://www.fiberglassrv.com/forums/...rot-91655.html). I thinkI have a plan in place to replace the possibly rotten floor. After that, we need to close the wall back up. In the attached photo of the completed demo, you can see the extruded polystyrene that is glued in relatively large pieces to all the walls. This was covered with glued on lauan. There are large gaps in the corners that had been filled with fiberglass batt-style insulation. The ceiling has polystyrene board, and some thinner white foam. The ceiling was originally covered with a carpet like headliner. I want to more or less emulate the original wall covering method with lauan, but i want tighter corners. Originally there was a angled piece of wood in there, stapled to the lauan on the walls, then had a small piece of lauan glued to it. See second photo of close up of corner (not sure how to rotate - carpet goes up).
My first thought is to get some more foam board, cut to fit closer to the corners...I will still need a corner piece of some sort?

Second part - dust. In taking the walls off, it is shocking how much dust was collecting in behind the wall panels. Well, maybe not that shocking considering the number of vents/holes (fridge, HW tank, furnace, lights). The fridge especially is thick with dust. Is there a way to prevent this? I guess it wasn't really coming into the living space, so maybe not that big a deal?

[Baxter]

What about spray foam? Seems like it could solve both problems.

[Joannad]

How do you maintain access to wires if you use sprayfoam? All the wiring goes up and down the 'corners', seems like we should maintain access for repairs/rewiring if necessary down the road?

[Baxter]

Dunno. Haven't done the spray foam thing myself, but I know others on here have.

I don't think it'd be a concern. Almost all electrical problems happen at a connection, not in the middle of a wire run, and in the rare occurrence you did need to get to a wire, you could either just fish it out, or cut out the foam to get to it then refoam it back in.

Really, it it any worse than running it behind ensolite? You definitely can't get behind that stuff, at least not in one piece, and you can't replace it either.

[thekas]

I have done numerous spray foam jobs. Once did a camper van & as in my house the use of a conduit will solve the issue of wire access. You can use pvc pex abs any type of smooth pipe or hose. For the corners electrical junction boxes work well & can easily be made accessible. The plastic type work best you can grind them to fit in snug spaces. The advantages of the urethane spray foam are numerous. One inch thick urethane foam is more than adequate & will add tremendous rigidity to the unit. Also will seal the unit from any moisture instuding, sound deadening is another. A body type rasp work well to shave the foam is necessary. And the time savings involved alone makes it my only choice !

[k corbin]

Just build in channels for the wire runs that are not completely embedded into the insulation. They could even have removable covers. I insulated my Campster trailer but kept the wiring inside of the cabinets and not visible also they can't be snagged when putting contents into the cabinets. My wires are not inside of the foam insulation or under the wall covering. Of course I could have done that but chose not to do so.