Ready to Insulate.. Need some Advice...

[Highway Yacht]

I needs some advice here from some of you that have "built" your conversion.. I've gotten my bus completely stripped on the inside. Windows have been removed, new skins have been installed as well as a couple new RV windows also have been installed. Floorplan is taped off on floor. I've already purchased basically all the mechanical for the interior such as the 3 way fridge, gas water heater, holding tanks, gas stove and oven, heater, toilet, shower, cabinet etc. I've also purchased enough foam board to do the insulation. My question is, should I go ahead and install any of the fixtures such as the gas water heater, 3 way fridge vent, or anything else that will require a vent hole cut into the shell before I install the insulation and plywood?? My thinking is that it would seem to be easier to cut out the vents needed now instead of trying to cut vent holes after the insulation and plywood are in place. Also, what about the wiring?? Shouldn't the majority of the house wiring go in AFTER the insulation and BEFORE the plywood?? Any advice and tips would be appreciated..

Thanks,
Jimmy

[robertglines1]

Sounds like you got a plan.    Foam in a can is your friend to fill any voids in your insulation or short or mis cuts;also make good adhesive if foam insulation is the non plastic coated type.  Bob

[chart1]

Make sure to put extra conduit in for wire runs in the future or for something you missed I wired my whole coach first them sprayfoamed

[Seayfam]

Hi Jimmy,
My bus was done pretty much like Cory's. It was wired first. When I build houses, I do all the plumbing, wiring and install all vents before insulating. I would probably do the same with a bus. Use metal boxes, conduit and wireways wherever you can. Then cut your foam to go around everything and fill the gaps with spray foam.

That's just what I'd do. FWIW

[Chaz]

I did like Gary spoke of. I bought 3 thinkness's of foil backed foam board. 1/2", 3/4' and 1". I used whatever thickness's I needed to get the max thickness. Then i used spray can foam to "tighten it up". It was very easy and about as cheap as you can do. Actually, I thought it was quite fun!
But either way, I think conduit is the best way to go before you insulate. Vent holes, etc. are easy enough to cut later. And if you mess up a cut in it, just stick it back in and cut again. (provided you didn't cut the inner or outer wall.  )

[JohnEd]

Put 4 inches in the ceiling.  Paint the roof with Emron Pure White.  Sell the foam board you have and spray foam the walls and get that 4 inches in the ceiling.  4 inches of foam is R30 and you only need three roof AC units in 110F ambient.  Just a swag to make a point.  Ace has pics of his done with foil backed foam board.  Polyisocynanate(?)  He cut the stuff perfectly and taped the edges to the frame with what looks like furnace tape Stainless Steel with adhesive. Seemed a shame to cover it up it looked so good. His job looked so tight it would not have any space to squirt the stuff into. The foam that comes out of a can needs air to dry and harden so putting it behind the foam board MIGHT be counterproductive or ineffectual at keeping the foam in place and it might out-gas and lift the foam that you were trying to cement in place.  "might" was the operative word.  Many here have done this and I hope they will share their experience with you.

Do us a big favor, if you would.  Get an estimate to have it spray foamed.   Then share with us what type of board you are installing, the R value for your stuff and what you will spend on materials and what those materials might all be.  Nice to know how long it will take you to do it, also.  Many others will face your dilemma and your answers will be most helpful to them.  It used to be that it cost less to have it sprayed and you got the increased R factor, quieting, structural integrity/strength bump  and missed the labor as a bonus.  I would go with spray for those added benefits and performance but I wonder that the cost trade-offs haven't changed in boards favor since this was hashed the last time cause we are living in "changing" times.  Or have you done this comparison already?  Share?  

Thanks,

John