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What Sizes Do School Buses Come In? (Bus Conversion Notes)

What Sizes Do School Buses Come In? (Bus Conversion Notes)

When it comes to choosing a school bus for a conversion, the options can be overwhelming because there are so many factors to take into consideration. In this article, I will share what I’ve learned about bus size options, both through my own research when I was buying a bus and from friends on the road with buses of all sizes.

So, what sizes do school buses come in? Here’s the 3 primary types…

  • Mini Skoolies
  • Mid-Size Skoolies
  • Full-Size Skoolies and Coaches

Mini Skoolies

Mini skoolies include buses from 20 to 25 feet in total length. These are generally suitable for one or two people, and maybe one pet. It can be a challenge to fit everything you want into a smaller bus like this, so building in storage everywhere is key. However, smaller buses are more agile, so they are easier to drive and park, especially in cities.

My boyfriend and I live in our 22-foot bus full-time, and we couldn’t be happier with it. We managed to fit all of our main priorities in it (fixed bed platform, composting toilet, fridge, counter space, large couch) without much compromise.

The only things we sometimes wish we had are a wood stove and a passenger seat for long drives, but we weren’t willing to give up maneuverability for those things and we’ve gotten along just fine without them for over a year.

Stu The Bus at Alabama Hills

We added significantly to our square footage by building on a rooftop deck. We store our bikes and our spare tire up there, and we used to have a crash pad for climbing up there as well. If we were really in need of more storage we could add a rigid locking rooftop box, but so far the storage we built into the bus has been more than sufficient.

The deck is a great space to hang out, stargaze, tan, etc.

Mid-Size Skoolies

Buses that are 25-35 feet fall into the mid-size category. This size of bus is perfect for two people and a few pets, although I have seen some couples with small children who can live comfortably in a mid-size bus. These buses generally look more like full-size buses in terms of style, wheel size, and engines, but they are slightly shorter.

Our friends Zac and Tiffany of @rolling_vistas have a 31-foot bus, which, at first glance, is easy to mistake for a full-size bus. It has a flat front and massive tires, but the shorter length is perfect for them and their two dogs.

They chose to have a Subaru as well that Tiffany drives behind the bus when they are on the move, which gives them the versatility to be able to boondock out in the middle of nowhere, but also zip easily into town in the car to get groceries, or navigate rough mountain roads that otherwise would be inaccessible with just the bus.   

Rolling Vistas bus next to Stu. It’s quite a bit bigger!

Full-Size Skoolies and Coaches

Any bus over 35 feet qualifies as full-size. The largest school buses are built for 97 passengers, and those are 42 to 45 feet long depending on the exact configuration. While they aren’t technically skoolies, coach buses can also be used for conversion, and those are generally 45 feet long. These behemoths are great for families or if you plan to work out of your bus.

We have seen families of six living in full-size buses, as well as hair salons, leatherworking stations, and jewelry shops built into conversions in addition to a living space.

Full-size buses obviously require more planning and consideration when you are choosing your driving routes and finding parking or camping. Most people we’ve met with 40-footers have a tow or follow car so they can park their bus at their campsite for the duration of their stay and run errands with the car.

Our friends Adam and Elizabeth and their two daughters (of @deliberatelifebus) live in a full-size bus with a roof raise. They have bunk beds for the girls and a beautiful kitchen with full-size appliances. They have both a follow car and a dirt bike, so they have a few options for scouting out locations and running errands.

Deliberate Life Bus

Exterior of Deliberate Life Bus. Courtesy of @deliberatelifebus

How To Estimate Bus Length and Square Footage

Most bus-for-sale listings only include a passenger capacity, not the bumper-to-bumper length and interior square footage. This can make it hard to shop if you are looking for a specific length, especially if you can’t go see the bus before making the purchase. Fortunately, there are ways to estimate the length and square footage from looking at a picture.

Window Rule – As a rule of thumb, each window on a bus body is equal to about 2.5 feet of length. Most buses are 7.5 feet wide on the interior. So, to quickly get an estimate of a bus’ square footage, use the equation [number of windows] x 2.5 x 7.5. For instance, my bus has 5 windows, so 5 x 2.5 x 7.5 = 93.75 square feet.

Our actual square footage is closer to 100 because our fifth window is extra long to accommodate the wheelchair lift door on the other side of the bus, but the equation is a good starting point if you are shopping for a bus and the seller doesn’t provide exact dimensions. If your potential bus has a wheelchair lift, that can be an additional 0.5 to 1 foot of length.

Front End Style and Engine Placement – Where the bus’ engine is also affects the total length of the bus and the usable square footage of the interior. Some buses have engines in the front while others are in the back, and front styles vary from a van front, snub nose, dog nose, or flat front.

To estimate the total length of a bus, take your window count and multiply it by 2.5, and then add length to account for the type of front end: roughly 10 feet for a dog nose or van front, and about 6 feet for a flat front.

If the engine is in the front, that’s at least a few feet of the total length of the bus that isn’t usable interior space. Depending on the arrangement of the front end, the driver’s seat and entryway steps can take up another few feet. In my 22-foot van front bus, the engine and driver’s area take up a good chunk of space, so our buildable area was only about 13 feet long.

In a flat front pusher bus (with the engine in the back), the driver’s area only takes up a couple feet of space, but you also have to take into account the engine in the back, which can eat into under-the-bed storage space (or whatever you decide to have back there).

These buses are also a bit different to drive, since you as the driver are situated in front of the front axle rather than slightly behind it as in a normal car or buses with the engine in the front.

Factors to Take Into Consideration When Choosing a Skoolie Length

Where Will You Convert It? This is a critical piece of converting a bus: having a place to work on it. Some friends of ours bought their bus and tried to convert it while it was parked on the streets in a city in California, but they racked up hundreds of dollars of tickets for various offenses, including parking in one place for too long, doing construction in the street, etc.

Now they are still working on converting the bus in the streets in Boulder, but have already gotten at least one ticket here already. Plus, they don’t have a steady power source to charge up their tool batteries, and they are living in the bus with their four cats while they try to do the conversion which makes it harder to get anything done.

I have also heard of homeowners’ associations taking issue with people parking buses on their own properties for extended periods of time, so if you live in an area where that might be an issue, check out the rules in advance. If you don’t have space where you live to convert the bus, ask family and friends if they have any space that you could use or rent, or check sites like Craigslist for workspaces.

My boyfriend and I were very fortunate in that his parents allowed us to park our bus on their property for the 8 months that we were converting it, and his dad allowed us to use his shop and all the tools in it. This saved us a ton of money and stress. There would be nothing worse than buying a bus and getting super excited to do your conversion, only to discover that you have no place to store a huge bus.

If we had gotten any bigger of a bus, it wouldn’t have worked out so smoothly to park it at my boyfriend’s parents’ house.

We parked on this gravel pad next to Aaron’s dad’s shop which is barely visible behind the bus. So convenient!

Cost of the Bus, Conversion, and MaintenanceBigger buses are often cheaper to purchase than smaller buses. Most people that I’ve talked to with mid- or full-size buses paid in the neighborhood of $2,000 to $3,000 but the bus is at least a few decades old, whereas smaller buses sell for $5,000 to $8,000 and are usually newer.

That may just be an anomaly based on who specifically I’ve talked to, but even when I was researching to purchase my own bus, that seemed to be generally the case.

However, if you pay less and get a massive bus, you will probably then spend more on the conversion just based on the quantity of materials that are required to build out a larger space. Check out this article that outlines the costs of a few different sizes of buses to give you an idea of what to expect.

Maintenance costs also vary dramatically based on the size of bus you choose. Our small bus has a Ford E-450 van front, so we can take it to any Ford dealership or a regular shop to get oil changes and other basic maintenance done.

While we have been turned away from a few shops because they either didn’t work on diesel engines or they didn’t have big enough bays to fit the bus, we have always been able to find mechanics when we need them without much hassle. As you can imagine, you can’t just drive up to a Jiffy Lube with a 40-foot bus with an 18-inch roof raise.

You will need to find specialists with huge bays, which are generally more expensive than a regular shop.

“Our bus has light truck tires, so when the treads get worn low, we have been able to purchase gently used tires with better tread for a steal, which has saved us tons of money.”

Eventually we plan to replace all 7 tires (6 with the duallies plus a spare) so they match, but for the last year we have spent maybe $300 total on a spare tire and rim plus two other replacement tires. Mid- and full-size buses have gigantic tires that are about $500 a piece to replace, and it’s much harder if not impossible to find used tires for sale. That’s a seriously expensive flat!

If you break down in a big bus, getting a tow can be much more expensive and potentially difficult, if there isn’t a large enough tow truck in the area. We’ve heard stories of full-size bus owners having to wait multiple days for a tow. Even our 22-footer weighs in at around 6 tons and would require a pretty hefty tow truck.

We have a Good Sam’s Club membership which is similar to AAA in that we pay an annual fee and then have a safety net if we need to be towed or get some roadside assistance. So far we haven’t had to use it, but it’s reassuring anyways.

Number of People and Pets On Board – It simply wouldn’t be practical to have a family of six live in a mini school bus, but I do know couples who have full-size buses because they want the extra space. Make a list of all the amenities that you can’t live without, draw a few scale diagrams with the width set at 7.5 feet, and see how much length is necessary to fit everything you need.

If you plan to bring pets with you, be sure to account for space for them to sleep, a place for their food and water bowls, storage for bags or cans of food, a litter box or kennel if necessary, and so forth.

We have seen some really cute dog kennels built underneath the bed in the back of buses, usually in a mid-size rig. That space is where we store all of our clothes in dresser drawers, and I’m not sure where we would store them if we had a dog kennel down there, so we would probably have to up-size if we ever get a dog.

Beds also obviously take up a lot of space. Just our queen bed takes up 5 of our 13 feet of length, so if you have to add in bunks for kids or more than two adults, a full-size bus basically becomes a necessity.

Additionally, the more people and pets on board, the more water, food, electricity, clothing, etc. you will need. For reference, our 20 gallons of fresh water will last us about a week on the road if we don’t take any showers and just use it for cooking, drinking, washing hands, and washing dishes. Families often will go through 100 gallons of water in a week.

How Much and Where Do You Plan to Drive? If you are planning to convert a bus and then just park it somewhere longterm and live in it, size isn’t really a limiting factor and bigger is probably better. However, if you plan to move around a lot, you’ll need to consider the maneuverability of the bus, length limits at campgrounds and parks, and so forth. 

Bigger buses are also heavier and require more fuel to move around, which in turn is more expensive. Somewhat counterintuitively, most of the larger buses that I’ve toured have 20-30 gallon fuel tanks, while our relatively tiny bus has a 55-gallon tank.

We get 10-12 miles per gallon depending on the driving conditions, whereas the big guys usually get 8-10, so while we can go about 600 miles on one tank, they are having to refill every 300 miles or so. Our rig fits easily into most gas stations, but some large buses with roof raises have trouble fitting under the awnings at gas stations or just making the sharp turns required to get up to a pump.

Additionally, only having a 300-mile range means that you might be forced to pay more than you want to for fuel just because there aren’t always multiple options in the middle of nowhere. Be sure to check the fuel tank capacity when you are shopping for buses.

If you are planning to boondock or camp in remote areas, you will also need to be aware of how much room you will need to turn your bus around.

Some forest service roads are narrow and lined with trees on either side, and you may have to drive for miles before you can turn around, or you might not be able to at all, which means you will be backing a huge bus all the way back down the road, which is difficult as well as dangerous.

Will You Have a Tow or Follow Vehicle?Most people with mid-size or full-size buses that I’ve met on the road have a car as well that they either tow or drive separately behind the bus (which can make merging easier for whoever is driving the bus, by the way). Having a car makes it much easier to run to the grocery store or do other errands that aren’t practical in the bus. However, then you are paying for fuel and insurance for two vehicles.

Our 22-footer fits into most parking spaces, especially if we back in and can hang the back end over the curb, so we can take it to most groceries stores and just park in the back of the lot to have a bit of extra space. There are some parking lots and spaces that we just can’t fit into (in big cities usually), but if that’s the case then we just go to a different store or look for street parking nearby.

Sometimes we wish we had another vehicle that had four wheel drive and high ground clearance so we could get to some of the more rugged trailheads and hot springs, but having our house with us everywhere we go is more than worth the few spots we have to miss out on.

We have bicycles that we use for getting around in cities or exploring trails, which has been super convenient so far, and we just strap them to the deck when we are on the move.

Another factor if you choose to tow a car is whether your bus has the engine power to do so. If you build out the bus with heavy materials and then fill it with all your belongings, you might already be approaching the maximum load that the engine can handle, especially going up hills. Adding a tow car may reduce your uphill speed quite dramatically.

We had an impromptu buslife gathering at a rest stop. Three buses, one follow car, and one motorcycle.

There are definitely pros and cons to all the different sizes of buses available, but I hope that this article has given you some helpful guidelines and things to consider as you shop for your perfect school bus to convert!


Related content:

How Much Does It Cost To Live and Travel in a Bus?

Buying Our School Bus For Skoolie Conversion ($5K Budget Enough?)

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  1. Brian Lindsay says:

    Toying with the idea of chopping off the overhang of a full size, basically shortening a bus without changing the wheelbase…..any thoughts?
    Another thing your article might include is height inside, as in head height.

  2. Jose Valdes says:

    I live in Mexico, so skoolies are attractive in hotter climates due to the insane amount of openable windows, I don’t have to worry about Alberta temperatures.
    Yours is one of the best-explained articles in the internet about skoolie size.
    Stay safe, guys!

  3. Zé Calazans says:

    Hello! I’m coming back with an old plan to cross the Americas on board a motor home. I think the converted Mini School Bus is the best in safety and comfort. At the moment I am just gathering information and arguments for the best decision. Here in Brazil we have good conditions to carry out a project to transform a vehicle into a home engine, but I need to know more about the intended model. Thank you!
    Big hug!

  4. John Trusty says:

    I have just started considering bus life after retirement in 4 years & this informstion was very useful in looking for what size, type of bus to purchase as I want to convert myself to my specifications. Thank you!