We have 3 children, all young enough to be in car seats. In 2011 we took a 3 week road trip in our mini-van. We had a few required stops on our trip, but generally we were very flexible on where we stayed on a given night and what we did on a given day.
This was a great trip; to most people the idea of being stuck in a van with 3 small children for thousands of miles sounds terrible. But we really enjoyed it. There were, however, some logistical issues that we felt could be improved.
Firstly, children need to get up and run around. And this requires space, for the kids, but security, for the parents. A fun part of the trip was pulling into small towns and finding city parks on our GPS, then taking short breaks at parks where kids would run around and be kids and adults would discuss the day's progress and goals.
But sometimes, there isn't a nearby park when its time for a break. The weather can turn on you, or the rest areas at the interstates can have a creepy vibe. And there's a fixed amount of space for toys and familiar things for the kids. So there was a general notion of needing more secure, inside space when we made stops along our journey.
One thing that added to the stress level of the trip was needing to eat at restaurants so frequently. We hate being "those parents" -- the ones with loud, unruly children. Managing 3 hungry children, who are all still developing their sense of "inside voices" and "frustration management" can suck the fun right out of a trip. Having a credible option to eat privately instead of publicly would save both money and stress.
Our youngest two were in pack-and-plays that summer, and any parent understands that kids need a lot of stuff. In the van, every night after a long day of driving, we needed to cart piles of stuff into a hotel room, set it up, and get kids to bed. The setup and acclimation had to happen while kids were getting into things that hadn't been kid-proofed yet, and when it was finally bedtime, the adults were stuck having to be elsewhere and silent. We eventually figured out that suites or adjoining room pairs made the hotel aspect of the trip much better, but of course, much more expensive, and much harder to find hotels along the route without prior reservations.
Finally, there is the issue of going to a bathroom. It's never fun to use somebody else's bathroom. Finding bathrooms on the road can also be... stressful.
So by the end of our trip, we knew that we wanted some kind of RV.
Our van has a limited tow capacity -- 3500lbs. We looked at trailers of different sizes and types, but nothing that had enough room and facilities was light enough to go behind our current vehicle. To pull a 5th wheel or larger trailer, we'd need a better tow vehicle. But our tow vehicle would have to hold 3 car seats, which might technically have been possible with a new jumbo SUV or crew cab truck, but those are quite expensive.
Class A motorhomes are of course incredibly expensive. Smaller motorhomes, when used, can be affordable, but finding one outfitted the way you want is especially tricky. For us, the deal breaker was adequate child safety. Most motorhomes have 1 driver's seat, 1 navigators seat, and then some couches or dinettes. We required that all members of our family be seat-belted and forward facing, and the 3 kids be in the car seats, at all times when the vehicle was underway. We just didn't find any motorhomes that had sufficient seating and restraint systems.
Another point on motorhome safety: most people in the bus conversion crowd call conventional motorhomes "sticks and staples". If you look at how they are constructed sometime, you may come to the same conclusion. But if you ever see one in an accident, you'll certainly agree that you don't want to be in one during a wreck at highway speeds.
I'm not quite sure where I first came across bus conversions on the internet; it may have been a link to the steampunk bus (iirc, that guy does some other steampunk stuff, some of which may have shown up on slashdot or other geek sites). I actually knew about bus conversions prior to our 2011 trip, and so as we took that trip and noted the shortcomings, my wife and I started joking about "if only we had a bus right now.."
Bus conversions have some advantages over a conventional RV. Firstly, used busses are very affordable. They are usually built well, primarily out of metal. They have medium or heavy-duty drivetrain components and they are built to carry lots of heavy humans. Coach busses even have built-in bathrooms sometimes. School busses are built to keep children alive who aren't wearing seat belts.
Once you take the seats and other equipment (e.g. heaters or luggage racks) out of a bus, you have a nice open floor space to deal with. You can refit the space however you like.
However, there are some disadvantages to coach busses, besides their higher initial cost. The extra size can work against you anytime you leave the interstate. Coach busses have poor ground clearance and aren't suited to marginal roads. This can be a serious consideration if you will be driving down section line roads in farm country, or if you want to take unpaved roads in government parks.
Ultimately, we opted to look for a cheap, commonly available school bus with a shorter wheelbase and higher ground clearance. My wife is taller than I am, so it was critical that we have _enough_ interior height, but any height beyond that would just limit where we could go.
Hydraulic brakes are what normal cars have. Some busses have air brakes, which is what larger trucks and semis have. Air brakes are what you hear when trucks start or stop. I am comfortable working on hydraulic brake systems and understand them. Air brakes are something I have no experience with, and apparently they are not self-adjusting. So, that didn't sound fun to me :)
The DT466 is an in-line 6 diesel engine made by International Harvester (now Navistar). The basic design has been around since at least the 70s, and still ships today as the MaxxForce DT. This is a medium duty engine and internet reports indicate that it is used in tractor pull competitions at well over 1000 horsepower. In school bus trim, 190hp and 500ft/lbs of torque was a common configuration. The engines are highly reliable and very common, making them good candidates for my first adventure with medium duty trucks (which is what a school bus is). Finally, the DT466 uses replaceable cylinder sleeves, a feature commonly found on heavy-duty trucks and off-road equipment. The upshot of this is that you can rebuild a DT466 without removing the motor, making engine overhauls more affordable.
School busses come in a few body configurations. Besides the obvious long/short/medium lengths, there are conventional busses, which have the engine, hood, and front axle ahead of the windshield, and flat-front busses. Flat-front busses further can be divided into front engine and rear engine setups.
I wanted a full-length conventional bus, which would give me 1 door at the front and 1 door at the back, and where the engine wouldn't occupy any of the interior space, and where the engine would be easy to access and work on.
It turns out that the configuration I wanted -- DT466 engine, manual transmission, conventional full length body, and hydraulic brakes, was a reasonably common configuration in the 1980s. After a few months of searching, I was able to find one about 2 hours away on craigslist. It's a 1986 International S1853 with a Thomas body.
The main difference between our requirements and what most people have is that we wanted a proper seating area for when the vehicle was underway. The interior space of the bus is 7.5ft wide, and 30ft long from the back of the driver's seat to the back door. Putting in permanently mounted forward facing seats takes up a substantial amount of room, but having this feature is the main reason we didn't just buy a pre-made RV. (Admittedly, doing a bus conversion is _cooler_ than just buying an RV, but now that I've been through the experience, buying one would have been cheaper and certainly easier. I just wouldn't have been as satisfied with the outcome.)
To try and understand the available space, I started using computer software to model the floor plan and the interior of the bus. This was a first-order sanity check on if we had a workable layout or not. I use "Sketch-Up", which at the time was owned by Google. If you watch the online tutorials, it is excellent for casual-use users like myself. I can draw things intuitively but enter accurate dimensions taken from measurements I made from real objects. There is also a large library of pre-made models that you can import into your drawings. The seats, sink, and toilet, for example, are pre-made objects I merely imported into the drawing.
Here is an early sketchup drawing of our conceptual plan
I'll explain the floor plan features, moving from left to right.
Some observations on this plan: First, the children's bunk room is separated by the bathroom and kitchen from the "multi-use" area behind the seats. This multi-use area is where we actually setup a convertible bed for my wife and I. It's good for everyone if the kids and the adults have some space between each other when kids are supposed to be sleeping.
Furthermore, there is a center aisle/walkway that runs the full length of the bus. In the drawing the partition walls have no doors/openings, but that's because I didn't draw them in. In reality, one can walk from the front door to the back door down the center aisle, although there may be some doors or curtains to navigate through.
When we left town, we had the major features of the plan implemented, but not in a way that precisely matched the picture. We didn't build any partition walls; instead we had partition curtains. We didn't build bunk beds yet; our twins stayed in their pack and plays which we we left setup and secured while under way. Our older son slept on a mattress on the floor. This seemed to work out just fine, although for 2013 we expect to have bunk beds in the bunk room.
This is a view from the back of the bus looking forward. You can see the mattress on the left and one of the pack-and-plays on the right. You can also see the partition curtains in their stowed position. Moving forward you can see the toilet on the driver's side, as well as the galley kitchen. At the far front you can see the seating installed.
We had a few issues while underway: