Smells Like Teen Spirit: Conversion of 1999 Thomas MVP

[Redbear]

If I were putting an over-roof as in Nat's second drawing, I would not have the openings shown in the normal roof. That might allow too much air transfer out of living space or trapped air insulation space, and let too much heat out in cold weather. That might defeat the purpose of the roof insulation in winter, though the flow would probably help with keeping cool in summer. But side-to-side (or side to top vent) air movement between the two roof layers should be enough to keep down the heating/cooling demands on the normal roof. Check out how Elliot covers Millicent with a frame that supports overhead tarps at Burning Man.

I would insulate the roof as you have done (or foam it), BusKote the exterior roof, and then put solar panels and/or a roof deck to shade the bus roof. These additions would serve a dual purpose in doing so.

Just my one-fiftieth of a Federal Reserve note, worth what you paid for it.

[porkchopsandwiches]

I'm not doing a roof over my roof or a balcony or any of that stuff, I am just trying to find out what would be best for what I am doing.

Plastic: Good at keeping moisture from inside from getting into insulation, good at keeping any leaks from dripping through, but if the insulation ever gets wet it will have a hard time drying out.

Rosin paper: Breathes somewhat, will probably keep leaks out to an extent but could get waterlogged, insulation will dry out easily if it gets wet.

Tyvek: Breathes well, lets no leaks through, insulation will dry out if it gets wet.

I currently have a few leaks in my roof, small ones, that need to be fixed. I would fix them now but there is snow everywhere, and it has been / will continue to be below freezing most days, so more coats of elastomer are out of the question (water-based) and most sealants won't work. So I need something that will breathe from the insulation to the inside to dry out once I do get the leaks fixed. I am not concerned about short term water exposure. This is why I was considering tyvek.

[wmkbailey]

Originally Posted by porkchopsandwiches

Yesterday, I picked up 10 pieces of foam board polyiso foil-backed insulation, 2" thick, and got started putting it in the ceiling. Within about 2 hours, I got this far:

It goes pretty quickly when you don't have to worry about fasteners or adhesives. I turned on the kero heater and it already feels warmer.

Opinion: I was thinking about putting some sort of barrier (tyvek or plastic sheet?) between the insulation and metal ceiling panels, since the metal panels are perforated and could let small particles of insulation dust through, and there is a decent bit of this since I used a circ caw to score it so it would bend. Is this a good idea? I plan on sealing any air gaps with foil tape.

If you are not using fasteners or adhesives, how are you holding it up?

[porkchopsandwiches]

If you are not using fasteners or adhesives, how are you holding it up?

I friction-fit it in between the ribs of the ceiling for the bigger pieces. Smaller pieces will be taped or glued, then everything will be squished between the inner / outer skins eventually.

[bansil]

Sorry about down time...buy latex gloves for when you mess with great stuff.....seriously....I always say that after hitting the spray nozzle 1st time
And week later still peeling it off....not as bad as using rust convertor with no gloves...sheesh...purple hands for a week

Yeah I tend to actually get into my work

[Tango]

Roger the rubber gloves...and add Gorilla Glue (or any urethane glue) to the list. Turns your skin black. Cannot be scrubbed or solvented off. Only comes off when the skin comes off.

More than once I've used sand paper to try and clean my hands. Have I finally learned to NEVER use it without gloves???...well...

[porkchopsandwiches]

Originally Posted by bansil

Sorry about down time...buy latex gloves for when you mess with great stuff.....seriously....I always say that after hitting the spray nozzle 1st time
And week later still peeling it off....not as bad as using rust convertor with no gloves...sheesh...purple hands for a week

Yeah I tend to actually get into my work

Hah, thanks. I ALWAYS forget to use gloves. When I was sealing holes on the floor using rivets / urethane based automotive seam sealer, I was peeling that stuff off for 3 days. The oil-based paint i did the floor with was on my hands for easily 10 days. Both things work great and you can tell by how they linger.

The latex paint on the other hand peels off instantly, but hey, its cheap.

I almost never wear gloves when working on cars / engines though, it really bothers me for some reason and messes with my mojo

[PDBreske]

Originally Posted by porkchopsandwiches

I would have sprayed the whole thing on the inside if it wasn't for how damn expensive it was. The foam board I’m using, at $31 for 4x8 sheet ain’t exactly cheap....

How thick is the foam board you’re using?

If they’re only an inch thick, then the cost for 600 square feet of one-inch-thick insulation is $581. The spray foam kits are about $150 more than that (including the shipping charges) and you don’t have to spend anything extra on cans of Great Stuff. Plus, the spray foam adheres directly to the metal, preventing any condensation on the interior surface.

Obviously, this math doesn’t add up if you’re using thicker boards.

[ol trunt]

If I had it to do over I'd get a part time job to pay for the spray foam!!!! I don't think I'll EVER get rid of the little white foam balls that come with cutting and installing foam board--to say nothing of the fact that I'll always have to worry about moisture collecting in the unfilled areas.

[porkchopsandwiches]

Originally Posted by PDBreske

How thick is the foam board you’re using?

If they’re only an inch thick, then the cost for 600 square feet of one-inch-thick insulation is $581. The spray foam kits are about $150 more than that (including the shipping charges) and you don’t have to spend anything extra on cans of Great Stuff. Plus, the spray foam adheres directly to the metal, preventing any condensation on the interior surface.

Obviously, this math doesn’t add up if you’re using thicker boards.

2" thick, R-value of 13.1.

Originally Posted by ol trunt

If I had it to do over I'd get a part time job to pay for the spray foam!!!! I don't think I'll EVER get rid of the little white foam balls that come with cutting and installing foam board--to say nothing of the fact that I'll always have to worry about moisture collecting in the unfilled areas.

I agree, but my full-time job is barely able to fund this...I may be selling my car when I depart in (hopefully) June

[bansil]

Jack,
Fire that puppy up, hit the interstate with no windows installed, that should allow your (white styrene) balls to fly out the windows...see clean
Oh and wear goggles, safety first!

Edited to add "white styrene" just sounded wrong

[porkchopsandwiches]

No updates for a while, progress is slow. I had surgery 12 days ago and have been recovering since. I have almost finished insulating the ceiling. I wired all of the exterior lights (markers, added more side marker / turn signals, and white LED side accent lights on the pillars). I am almost done running wire for the interior lights and speakers, using the stock ceiling panels and speaker / light locations. When I finish this I will cram as much insulation / spray foam into the gaps and then install the ceiling panels, hopefully this week!

This is what $425 worth of CAT parts looks like:



$60 well spent:



Finished exterior lights at night:



And a big freakin mess:

[Tango]

Smells like Progress! Stay after it!

[browncrown]

As we all know, parts aint cheap, but keep the faith. Love your new horns

[sdwarf36]

Ok-I just looked quick-I thought you had a skateboard ramp installed!

[ol trunt]

Don't show any more of those Cat parts-------I think I'm going to,be sick------

[porkchopsandwiches]

Alright, been moving right along.



Finished insulating the ceiling, insulation is held in now with friction and some foil tape. Wires for lights are run in the insulation (grooves cut) and speaker wire as well. The original bus had 6 speakers, I am cutting it down to 4. Easier to find head units that power 4 speakers, and 2 of them would be in awkward spaces anyway (one in the shower). No worries though, I will have a bangin' supplemental stereo



Blue tape is to mark where lights / speakers go, wires friction fit in insulation held in by foil tape. I have vacuumed the ceiling since.



9 mahogany veneer solid core doors, 3' x 8' I scored for free. Planning on using these for countertops and maybe partitions for the shower / bathroom, but not sure about that due to how freaking heavy they are. They are 90 min fire rated.



My layer between living space and insulation, tyvek. Held on with foil tape (love this stuff, very strong adhesive on it). Cut holes for lights and speakers and taped around them.



Panels to be tyvek'd



Interior side of panels. They have been scrubbed with bleach and hosed down and dried off.

I have finished tyveking them but haven't put them back up yet. The first one I attempted to at 11 pm Saturday night but the first one is at a weird angle and wouldn't line up right and I got pissed off and was tired so I called it a night. I may try again tonight. The rest should go up easy.

Notes thus far:

This foam board stuff is nice, it is expensive but has great R-value. The kerosene heater I have been using on its lowest setting and it is getting to be too much, even with no floor or side insulation.

If (when, rather) I were to do this again I would definitely have it spray foamed professionally. This board works ok but there are plenty of gaps still and it takes a long time to cut the small pieces for the curves.

Next up is fixing one last leak, welding in a few metal bits, and then resealing a few windows, taking out a few windows and putting blanks in, and insulating the walls with the same 2" polyiso foil board. Then, 1/2 or 3/4" foam on the floor overlayed with 1/2" osb. Then, let the building commence

[porkchopsandwiches]

Update on the ceiling project- DO NOT UNDER ANY CIRCUMSTANCES reuse the ceiling panels on a Thomas bus if you don't have to. They are an UNBELIEVABLE b!tch to put back up, lining up all the holes and getting the screws to go in straight. I finally got all of them, but with the time and frustration I spent I could have done 3 bus ceilings in pine 1x3s or whatever. What didn't help is the insulation is slightly deeper than the support ribs so you're trying to line up 2 overlapping panels with the holes drilled in the ribs, all while pushing hard enough to slightly compress the insulation. 1/10 would not recommend.

What's up with the site recently? The last few days I've tried to get on and it's been down.

[Tango]

LOVE the LED's! --- Just maybe one of the best "new" things to happen to RV's in years. Real battery savers and they seem to be getting better and cheaper by the day.

[Docsgsxr]

Hey Chop,

I bought the exact year and model you have. Did you ever get that injector/oil issue resolved in your fuel?
Seems like I have a larger amount of whitish smoke than normal coming from my crank case tube and I was
wondering if I might have a similar problem with my injector(s)?

Rocking job man! I am going to start mine this summer when I get back home from New Hampshire and can't
wait!!!! (I plan on using a few of your ideas. I think the external soft white led's are a great idea!)

-Doc