Meet our new bus... Mr. Beefy!

[TheHubbardBus]

Not yet mentioned is our on-demand hot water heater (that white box in the rear driver-side corner). We went with a Precision Temp RV-550 NSP EC. It's a higher-end unit that is frankly overkill for our small bus (I'm trying to figure out ways to justify it, like carrying a portable hot-tub on-board ), but from everything we've read it seems to be the most bullet-proof option. It's propane powered, and directly vents as well as takes in fresh air through the floor. It also directly drains through the floor in the event something goes wrong & the pressure relief valve opens. Ultimately it ends up under the area our couch/bed will be, as close to the rear of the bus - and thus as far away from intake air sources - as possible. It's the one and only thing that's not thermally isolated from the metal floor, so ultimately we'll be insulated around it. The flooring immediately surrounding it will be lined to form a basin that - while it should never see water during normal use - won't be harmed if something goes wrong.

[TheHubbardBus]

Round 1 of insulation going in. But much more to go.

We had originally planned on spray foam, but I had many concerns I ultimately just couldn't let myself take a chance on. Would it warp the exterior we had spent months of tender loving care on? Would the mix not be perfect and result in isocyanate offgassing? Would it eventually delaminate allowing moisture to promote rust hidden from view? Plus there was the issue of sound insulation being just as important as thermal performance. So... we went another route.

Our plan was to use Rockwool AFB (acoustic fire blanket) for our first layer of cavity fill throughout the whole of the walls & ceiling. R-value of ~4.5/inch, extremely heat / fire resistant, hydrophobic, and a superior sound-absorbent material. Not easy to find, especially during the pandemic, and especially in less-than-pallet quantitites. Ended up sourcing it from ats acoustics on the 'other' side of the country. But when I received the first shipment (thankfully I miscalculated and needed to order twice) they had sent Owens Corning 703 (the yellow stuff) by mistake. The good news was the 703's thermal performance and sound absorption properties were almost exactly the same as the rockwool we had requested, if not a hair better. It's also > twice the price which we got for the price of rockwool. BUT... it's fiberglass which we didn't want, not nearly as flexible, and not close to the same regarding heat tolerance.

Ultimately, however, it all worked out even better than we planned. We ordered another batch of rockwool - and got rockwool this time. We found that the OC703, due to it's stiffness, was a breaze to install + perfect fit on the 'flats'... walls & center of ceiling... while the rockwool AFB's flexibility was perfect for the curves, including areas where heat tolerance were desired, like surrounding the direct-vented propane fireplace ducting.

[TheHubbardBus]

Up to this point the bus has remained drivable, but I figured we didn't want to be riding around in a vibrating tube lined with fiberglass & rockwool. So we're taking this opportunity being overhauling the bus electrical system. The goal is to repair ('perfect' would be a better term) any of the dash/fuse panel wiring requiring it, wire in a whole bunch of new circuits (off-road lighting, air horn solenoid, fans, spares, etc) into the fuse panel just as they would be if original equipment, and clean/insulate the driver-side panel. We'll also be using the front dash panel area to mount/contain many of the house-system electrical components and wiring, so this is prep for that.

First thing we did was label every plug on both sides before disconnecting, take pictures before disconnecting, then take video before disconnecting! The last two steps were key, because labeling wiring with low adhesive, easy-to-tear blue painters tape is a freakin' stupid idea Also took a ton of pictures of everything - close up and distant, multiple angles - before beginning disconnection / dissasembly. The pictures included here are an insignificant fraction of those we took.

One bit of advice for what it's worth: It's just as (maybe more) important to label the plugs NOT connected to anything as it is the ones that are. Trying to figure out where a matching male/female connector is to a harness plug that never was attached to anything can result in a frustrating experience.

[TheHubbardBus]

And now it's time to make a little room to work...

(BTW - Just realized I never showed the required removal of the heater which was housed here. But yeah, we did that already). Just cut the hoses inside the firewall as we'll be replacing them w/ new.)

[TheHubbardBus]

Here's the view the heater/fuse panel sees when it's in place Prepped and painted the only remaining bit of steel flooring that hadn't yet been touched (excepting the driver-seat platform), and insulated any voids possible. That white cylinder potruding through the fuse panel door is the back of the shore power inlet. You can also tell we still had an intact circuit / fuse panel diagram on the inside of the door. That has proved imminently useful.

[TheHubbardBus]

Time for the chassis wiring harnesses to go. We had originally planned to leave them as received. But since I'm a masochist, I've decided instead to determine and document the function of every circuit, every wire, and every pin in every plug. I don't have a full chassis schematic, so I'll make my own! Then I'll rebuild the harness to include additional circuits not OEM, remove those not used/needed, make any required repairs, and replace all the connectors with water-tight locking replacements. Electrical gremlins will tremble in my presence. Not sure if this is one of the sub-harnesses or all of them, but it's before the work just summarized.

[Oldyeller]

When you say the 'chassis' wiring harness do you mean the wiring harness that goes around the interior of the bus?

[TheHubbardBus]

Insulation, Round 2.

The OC-703 & Rockwool AFB were both 1" thickness, leaving 1/2" left before reaching the level of the hat channel. I had originally intended to leave this an airspace and place continuous foil-faced board insulation over the 'studs', but for a number of reasons this didn't end up being a good plan. So I changed gears and needed to fill in the rest. I never planned on using polystyrene anywhere in the build, but it was pretty handy for matching the curves. Down the center is what I wish the polystyrene could be... poly-iso. All seams are eventually taped and sealed, but there are many not yet completed in these pics.

The driver-side heater / electrical / fuse panel deal-io is also back in place and installed, after much cleaning. None of the wiring has been replaced however. Don't judge me on the wiring to the fan & A/C... that's just temporary to prevent heat stroke (this was done in the summer).

[TheHubbardBus]

Originally Posted by Oldyeller

When you say the 'chassis' wiring harness do you mean the wiring harness that goes around the interior of the bus?

@Oldyeller... correct. On our bus there's one subharness in the front cap, one in the rear cap, one running the length of the bus on the passenger side, and then the most substantial running the length of the bus on the driver side (which begins at the fuse panel where the source of all these circuits originate). They're all plugged together to run the interior circumference along the roofline.

[Oldyeller]

Originally Posted by TheHubbardBus

@Oldyeller... correct. On our bus there's one subharness in the front cap, one in the rear cap, one running the length of the bus on the passenger side, and then the most substantial running the length of the bus on the driver side (which begins at the fuse panel where the source of all these circuits originate). They're all plugged together to run the interior circumference along the roofline.

OK, that's what I thought. As you can see in my profile my bus is an '04 IC CE-200. I assume ours are similar. In my exterior fuse panel there is a fuse block dedicated to the bus chassis and another beside it dedicated to the body electrical. You're tracing out and removing the body wiring, not touching the chassis electrical?

[TheHubbardBus]

BIG MOMENT, HERE...
We're finally getting to work on the floor!

I know lot of people go with floating floor setups, but it just doesn't jive with my sensibilities. We've got a high-headroom bus and we're short-headroom people, so we have enough space to spare for a sleeper system that will still allow us to apply a continuous insulation layer on top of it.

It looks easy, but was anything but. I wanted to make sure we had a perfectly flat subfloor surface, so knew somewhere I had to do a bit of shimming to make it happen. I decided to do that at the sleepers themselves. It's really way too complicated and involved (likely unnecessarily so) to explain in a forum post, but using wire-tie magnets, a tape measure, masonry twine, a square, polyurethane adhesive (my flexible 'shims'), and TEK wood-to-metal screws, and a whole bunch of time & curse-words, I acheived my goal!

First layer of insulation is 1" EPS. This is the only place I'm using EPS in the build, and the only (good) reason I'm doing so is because the r-value can actually exceed poly-iso once it gets cold enough. As the first layer up against the metal floor, this is likely the coldest surface we'll be insulating, so it might be of minor benefit. I do have one not-so-good reason, though... we dig the pink panther, and wanted to include him somewhere.

On top of this we reach the level of the sleepers by adding 1/2" poly-iso. Then tape the seams.

Four 2x10 blocks are used in the rear. These do double duty... they serve as the hangers for the under-skirt A/C condensers (same location originally), and also as additional support underneath our fresh water tanks (we'll have two 35-gallon tanks inside the bus, one on either side). Studs for the underskirt condensers are installed in counter-sunk holes, so we can remove/install them without needing to access the bolt heads again. There's another block forward of the driver-side wheelwell that's done the same, also with studs installed, below which we'll be hanging our horizontal propane tank. Two more blocks are set where the passenger seat will be mounted, and where the toilet will be mounted (probably overkill on the toilet lol).

In the rear there's a channel between sleepers through which PEX lines will run. 1" for the line connecting the two water tanks, and 1/2" hot/cold for an outdoor shower fixture through the rear passenger wall. There's 1/2" of polyiso lining the bottom, leaving 1" height for the PEX.

Finally, I measured & documented the locations of every one of these studs and spaces - in writing & pictures - so we know what to screw into, and what not to.

[TheHubbardBus]

Originally Posted by Oldyeller

OK, that's what I thought. As you can see in my profile my bus is an '04 IC CE-200. I assume ours are similar. In my exterior fuse panel there is a fuse block dedicated to the bus chassis and another beside it dedicated to the body electrical. You're tracing out and removing the body wiring, not touching the chassis electrical?

Yes, exactly the same. I bet I used the word chassis when I meant body. My apologies. I keep getting those two confused! Thanks for the correction!

[Oldyeller]

Originally Posted by TheHubbardBus

Yes, exactly the same. I bet I used the word chassis when I meant body. My apologies. I keep getting those two confused! Thanks for the correction!

Not meant to correct, just to understand what someone else with essentially the same system is doing. I'm always looking for ideas to steal - I MEAN - borrow.

Did you leave the wiring for the side and roof marker lights intact. I've been thinking I might tie into those for some additional functions, depending on voltage/amperage requirements. I've also had passing thoughts about how I might repurpose the flasher system. Maybe disco will come back.

And that flasher monitor above the driver seat is so cool I hate to get rid of it.

[TheHubbardBus]

Unlike the walls & ceiling, none of the insulating materials in the floor - and definitely not the sleepers themselves - do much of anything to attenuate road noise. And A LOT of road noise comes up through the floor. So I really wanted to do something special to address this issue.

I still have a case of 'green glue' (not what it sounds like, google's your friend) sitting around that I had originally intended to use to create a subfloor surface that was essentially one big CLD tile. I feel it would have worked out great if not for the fact I didn't take into account the product's working temp range, which our bus would have well-exceeded when unconditioned in the summertime. It might have still worked - but I wasn't willing to pay the price of having to tear our bus apart to redo it if it hadn't. So I opted for another alternative... 1/4" rolled rubber mat (specifically, 'Elephant Bark', manufactured by Rubber-cal, and sourced via Zoro).

My thought process was that 1) It (the rubber) had alot of mass, which in and of itself blocks sound, and 2) compressing it between the sleepers and the plywood subfloor would provide for a boundary layer that would provide further attenuation. Point A is valid, and for that reason alone I'm not necessarily disappointed that I went this route. But upon further reflection & study, I realize that Point B is an engineering problem I never solved for, and likely couldn't for this problem. Assuming consistent loading (which is impossible), you'd have to have just the right amount of 'give' in the rubber, matched with just the right amount of loading, to make it work. Too little loading and/or too stiff of rubber and there's no flex, so it's just like the same thickness of wood. Too soft of rubber or too much compression does exactly the same thing!

I can't say the rubber doesn't offer some benefit apart from its mass (which, not to be downplayed, is a significant benefit), but if I had to do it all over again, I'd probably use a thinner layer of mass-loaded vinyl to achieve the same effect for a little less thickness. Or maybe just a thicker subfloor. Or maybe both.

Still - even though it didn't work out exactly how I originally hoped it would - I do expect it to be a huge improvement in terms of noise reduction. Just not as huge as the high-tech solution I originally envisioned might have offered.

One thing I will say - I was very pleasantly surprised by the almost complete lack of odor this particular product had. I had no idea what to expect and had read horror stories of competing (cheaper) products smelling like what they are... recycled tires. This stuff... pretty much zero smell, what miniscule amount there was, was not offensive in the least. That was the case both before & after laying out in our gutted bus for 2 days prior to install during a summer in the desert SW.

[plfking]

Originally Posted by TheHubbardBus

Electrical gremlins will tremble in my presence.

My electrical gremlins just giggle and point when they see me coming.....I KNOW they're talking about me.

[TheHubbardBus]

Originally Posted by Oldyeller

Not meant to correct, just to understand what someone else with essentially the same system is doing. I'm always looking for ideas to steal - I MEAN - borrow.

Did you leave the wiring for the side and roof marker lights intact. I've been thinking I might tie into those for some additional functions, depending on voltage/amperage requirements. I've also had passing thoughts about how I might repurpose the flasher system. Maybe disco will come back.

That flasher monitor above the driver seat is so cool I hate to get rid of it.

LOL. You and I would get along great I can tell already

We left the marker fixtures wired as-is, but replaced the bulbs with LEDS, and 'tuned up' the fixtures to make sure the rivets they used didn't loosen and compromise ground over time (a few I just replaced). I, too, wanted to use them for something fun, but left them as-is. Still... that option remains. They're on their own circuit so we can always just modify it upstream if the want arises.

I kept the flasher (Welden 7000), and added an override switch which wasn't originally present so I could deploy the red flashers / stop sign at will (check out the documentation for the flasher if that doesn't make sense & you'll see what I mean). Aside from the sign, the red flashers activate the tail-light section of our rear red flashers (now LED STT lights). The stop-light section of the same lights is wired into the regular stop-light circuit.

Since the amber flashers are single-circuit and already wired into their respective turn-signal circuits, I can't use them in the same way, unfortunately. I could replace them with dual-circuit ambers (turn/park) but I'm past the point where that would be easy & we already purchased these brand new. I tried just paralleling the amber flasher outputs into the left/right turn-signal circuits so each 'flash' would alternately illuminate every amber on a given side of the bus (which I thought would be a really cool look), but that didn't work due to flasher internals. I know I can achieve the same effect using a relay or two, and that's what I plan to do, but haven't gotten back around to that yet. Obviously, none of this is for on-the-road use... nothing works if the master flasher switch is off, which it will be any timeon a public road.

I'm obviously playing catch-up here, but getting close to where we're at now. Stay tuned. I think you'll probably like what we did with our sign

[Oldyeller]

Originally Posted by plfking

My electrical gremlins just giggle and point when they see me coming.....I KNOW they're talking about me.

You shouldn't have fed them after mid-night.

[TheHubbardBus]

Originally Posted by plfking

My electrical gremlins just giggle and point when they see me coming.....I KNOW they're talking about me.

Check your PMs for a special offer on gremlin inspections

[TheHubbardBus]

We got wood!

Over the top of the rubber went another continuous layer of 1/2" polyiso, which was again taped at the seams. Now the fun part. 3/4" ABX is screwed into the sleepers below. Both the screw heads and the the ~1/8" gap between panels were sealed with 3M 540 polyurethane. Sharon drilled pilot holes while I came behind her with the screws, so once we had the panels in place everything went pretty quick.

The sleepers (with cavity-fill EPS / Poly-iso), 1/4" rubber, 1/2" poly-iso, and then 3/4" plywood add up to a total of 3" of floor. The good news is the wheel wells somehow shrunk in height during the process

The small rectangular hole on the passenger side, just forward of the wheel-well near the wall, is a bulkhead fitting we added for re-routing the A/C hoses up to the blower/evap unit we plan to keep. You'll watch this hole grow in future pictures, once we fix the problem of not being able to fit a wrench in there to actually tighten the fittings The big square hole nearby is left for access to the fuel tank (sender unit?). We just have a piece of EPS wedged in there for now. When the floor is fully installed we'll add a nice plate to pretty this up.

Another big source of noise (& heat gain/loss) is those wheel-wells. Over the CLD tiles we glued as much k-flex as we could fit. Later before we box them over we'll add more if we can.

In the back you can see we've stubbed out PEX-A running under the floor. The white 1" is the balancing line between fresh water tanks, the blue & red will be going to the outdoor shower fixture (black box just above the floor in the passenger-side rear wall). We went with expansion fittings as I feel they're far superior to anything else, especially in a case like this where failure could lead to a leak within the floor. FWIW, 1" expansion fittings installed with the manual IWISS expander sold on Amazon is one heck of a workout!

[TheHubbardBus]

Insulation, Round 3:

1/2" poly-iso is added over the OC-703 to fill to the level of the hat channel, then taped & sealed. Kind of the same situation as the ceiling... we changed plans half-way through or otherwise would likely have just used one material to fill these cavities entirely. Still, every bit of r-value counts, and we do gain a bit more with the poly-iso over another 1/2" of rockwool/703.

Boxes were also constructed to cover and further insulate the wheel wells. Any space between the already-installed K-flex elastomeric rubber insulation and the interior of the boxes was filled with rockwool AFB.

In the rear passenger corner we ran a length of non-metallic conduit for future A/C wiring leading up to the rear cap. One single length of PVC tubing runs from the driver side floor, up to the rear cap, over to the passenger side, and down that corner to the floor. This will be for the vent tubing connecting the two fresh water tanks to the driver-side vented fill cap. In both corners are rebuilt / reworked subharnesses for the stop/turn/tail/backup/license-plate lighting. 1" ID reinforced PVC tubing serves as a vent 'pipe' running from the grey tank vent cap on the roof, down the driver's side rear corner, to a bulkhead fitting exiting through the floor in the water heater 'basin'.

3/4" poly-iso as added below the rails running the length of the bus upon which the out-board feet of the seats were bolted using plastic auto bodywork push-pins. I also forgot to mention earlier that the cavities behind were previously filled with rockwool, and 4 'drip holes' per window in the bottoms of these cavities to allow any water that may find it's way into the wallspace filled by 703/rockwool insulation a way out, and air to evap it to find a way in.

Finally, nailers installed on rear walls in preparation for installing... rear walls.