Conversion How-To

Building and framing your school bus kitchen can be a difficult job if you don’t know what you are doing (like us!). There are so many different types of wood, screws, adhesives, joins, cuts and more. We were in way over our heads when we decided to start our Toyota Coaster bus kitchen and thought we could get it all done in 2 days. Ha!

Building the frame for our kitchen has been something we have been looking forward to for such a long time! We had ‘planned’ to spend 2 full days at the bus; framing the kitchen, lounge, bathroom and bedroom, and were hopefully going to smash it out. Everything was prepped. The materials were bought. The car was loaded and we had been to Bunnings for the last time. We were set, and it was time to go.

So where do you start? 

After chatting to a builder friend about our bus conversion floor plan, it was decided to start with the most functional place first; the kitchen. Our thoughts were, once the kitchen was finished, we could then work on the lounge room and bathroom, leaving the bedroom until last. Getting the most practical and ultimately the hardest part done and out of the way first, would hopefully mean a much smoother fit out. Our bed will run across the back wall of our bus in front of the wheelchair access ramp and make it much more difficult to get things such as wood and appliances in and out of the bus, so leaving it until last seemed like the best option.

Why did we decide to build our bus kitchen ourselves and not get it built for us?

The way you decide to fit out your bus is all personal preference.

There are a lot of companies who offer the service of fitting out a bus for you. A lot of people also opt to use pre-fabricated or ready to go kitchens to save time and effort. Functionality, space, cost, electrical, plumbing – there are so many factors contributing to the bus layout and framing.

Shane and I chose to build our kitchen ourselves for a few reasons. Design; we are getting exactly what we want and where we want it. Money; motorhome and bus kitchens can be expensive. We saw this as a cheaper alternative to do it ourselves than to have someone build it for us. Materials; we had the option to buy a pre-fabricated kitchen from a kitchen place or even our local hardware shop Bunnings. However, we decided against this as we had read a lot of forums that had discussed the kitchens being too heavy and affecting their weight restrictions, and also not being structurally strong enough to withstand being in a motorhome.

Whatever you decide to do, it is definitely something to consider thinking about prior to starting. Trust us, it only gets harder and more complicated.

What’s in our bus kitchen?

We wanted a relatively open layout in our Toyota Coaster bus, with lots of storage, but also with everything required to live comfortably on the road. Our kitchen was to have a 175 litre fridge, a combined oven and stove, a sink, washing machine, and a microwave. It was also to have plenty of storage, overhanging cupboards, a backsplash, and external access to the batteries.

Sounds like we don’t have much at all to squeeze into a 2.4 metre space do we?

That’s when we instantly saw our bus kitchen was going to be tight, really tight. We had drawn countless diagrams, measured multiple times and were trying to work out the best possible way to squeeze it in. It was decided, we just couldn’t do it. Shane and I were trying to fit all the conventional items from a house sized kitchen and laundry into a caravan sized kitchen.

We came to the decision that the washing machine was to move. We would fit it elsewhere. This compromise would allow us to fit everything we needed to into the space we had. So now that was decided, it was time to get to it, and actually build it.

What tools and equipment do you need for building your bus kitchen?  

Shane and I have no experience with bus framing, or any sort of framing at all. We failed to seek a professional or someone who was more capable than us to help, so we decided to try our luck ourselves. With time restrictions and trouble organising schedules, we researched to come up with a plan, and a design for the frame.

We decided for the majority of the framing, we would use 19mm X 64mm pine wood for our main frame, and 35mm X 70mm wood for the things that were requiring a bit more structure.

The original plan was to use 35mm X 70mm timber for everything, however, after looking at our space, and working out measurements, we decided it was not a viable option and would take up too much room. Both of us have seen plenty of kitchen layouts using similar sized wood or no frame at all. The thinner pine framing would have to do. It was a bit more expensive than we originally wanted. It was decided for the space it would save us, it would be worth it. We were still going to use the larger 35mm X 70mm for our lounge and bed, as they will be carrying more weight.

As with everything, the structure and what materials you use for your bus kitchen and framing is definitely a personal choice. Whether you decide to use the thinner pine, or the structural wood it is up to you. We have seen a lot of people who have done bus conversions! They have used metal for their framing, and some have just used the walls for their cupboards and had no framing at all. So whatever you decide, as long as it is structurally sound and meets any sort of regulations your state or territory may have, it is all a personal choice.

It was time to splurge a little! We purchased a nail gun to help with our bus framing. We got nails in various sizes, big enough to go through any of the wood we purchased to tack pieces together. The reason we decided to buy this was for convenience. It would be so much easier to tack the frame together with nails before screwing, to make sure it was right and to make it easier on ourselves.  The different sizes gave us variety, and easily accessible options when required. This would have to be one of the best purchases we have made to date! It is definitely something we recommend for anyone who is going to be doing a bus conversion themselves.

We also purchased timber screws, and metal screws. The timber screws were for the frame when attaching wood to wood, and the metal screws were to attach the 7mm plywood panel we got for the walls, to the bus. The metal screws were also for any structural support pieces of framing that needed to attach to the bus’s metal beams.

For each joint, we also used wood glue for added strength.

Shane tells me I like to go over the top with our bus build. I figure, that this is going to be our home, and I don’t want it falling apart on our first rocky road, or ditch that we fall into. I want our Toyota Coaster bus frame to be structurally sound.

Where do you start framing in your bus conversion? 

The walls and wheel arches; that’s where we started.

The amazing thing about Bunnings, is they cut wood to size for you.

We had measured our walls and wheel arches and knew the measurements we needed our pieces. We decided on plywood.

Plywood is a relatively inexpensive option for bus wall framing and if thin enough, it is easy to bend and manoeuvre along the curves of the wall.

Originally we were going to go thin for the walls – 3mm, however decided after looking at it, and knowing it may be damaged easily, we decided for us thicker would be better. We have read many forums and seen a lot of people who have used 3mm ply for their walls and they love it and it works. This is a personal choice, and there are a lot of considerations such as weight and structure that need to come into it.

Unfortunately, there is no happy medium between 3mm and 7mm unless you get marine ply. Marine ply is amazing as it is made to be used in waterproof areas such as boats etc. Amazing things generally come with a price. For each piece, it was $10 more expensive, and we were going to need a lot of it. 7mm ply for our bus walls was decided.

We had Bunnings cut each piece for the walls to 73cm high. We knew this would take us to our window level. The benefit of Bunnings cutting it was one, it made it fit in the car so much easier! Two, it saved us so much time and effort, and three, it was ready to go when we got to the bus. It was also free! An amazing service provided. It’s a great idea to check with your local hardware store of timber yard, wherever you purchase your wood to see if this service is provided.

So we returned to our Toyota Coaster bus, 7mm ply cut to 73cm high in tow, ready to go.

We purchased sheet metal screws at 20mm length, and self-drilling metal screws at 32mm for the walls. These would be long enough to go through the ply, and into the metal walls of the bus without penetrating through to the outside. If we knew then what we know now, we would not have purchased the sheet metal screws. We found they are not strong enough to penetrate the metal walls easily and we have not used them since. We would have saved a lot of money had we known that earlier.

Our Toyota Coaster bus has curved walls; this makes it difficult to create right angled joints which are attached to the metal structure of the bus. A plan was put in place. By marking where our cupboards were going to go to, we then measured the depth in two different places; the floor and the window sill, to the edge of our cupboards. The difference in these two depths showed us how big of a support piece we needed behind our cupboards so that there was no curve with our frame. It worked out to be 35mm – the exact width of the wood we had purchased. So, we screwed a 35mm X 70mm beam across the ply at the height where it would start to bow. While difficult to explain, it meant that our bus kitchen cabinet would have a structure behind it where the walls curve, rather than sitting on nothing. It would be supported.

Now that our beam was attached to our ply, we attached our ply to our bus wall using the self drilling metal screws.

It took a little bit of effort and a bit of patience, but piece by piece the walls went into place. By pushing hard and flexing the plywood as we went, it matched the curve of the bus beautifully without cracking. If we had used thicker wood, it may not have had the flex to get the curve as well as the thinner wood. And if we had gone with the 3mm, it may not have had the strength to withstand the pressure required to screw it into the metal bus frame. So we were happy with our decision to use 7mm plywood for our bus walls.

Goodbye bus wall insulation!

The wheel arches protrude into our kitchen area a little. So we decided to build a box using 9mm ply to cover them. This is not a necessity, but we decided it would be easier to build around a box, than a curved wheel frame. It is not a structural piece, so we just used wood glue and the nail gun to tack them together.

The kitchen framing –  

Simpler is better.

Start by measuring everything. We measured all our appliances, measured the space we had, and made it as even and neat as possible. We drew a diagram, which had all our measurements on it so we could constantly refer back to it.

They say measure twice, cut once. And I am very glad we did because we got it wrong the first time!

Deciding not to over complicate things, we had hoped we would get it done nice and quickly.

Starting with wood glue on each piece, we used the nail gun and tacked each of the 19mmX64mm pieces together in the form of our kitchen.

Our screws we picked were 30mm X 8G.  8G is the thickness of the nail. And it was too thick! After we tacked each piece we also screwed the joints together. Unfortunately this was causing some of the ends to separate and split. Not good!

Back to Bunnings we went. We thought maybe thinner screws would fix the issue. We purchased the same 30mm length, but in 6G thickness. It didn’t work. For us, we are extremely new to this and it began to get overwhelming. So we decided to try and pre-drill the holes prior to putting our screws in.

It worked! No more wood splitting. This is something we have continued to do throughout the rest of our framing since and is definitely a recommendation for anyone who is going to embark on a similar journey. Sometimes, we forget or get lazy and don’t pre drill. Almost every time we regret it as we have the same issues with the wood cracking and splitting. So take it from us – pre drilling works – do it!

The pieces came together, and our bus kitchen framing took its shape.

Once we were satisfied with the framing and had double checked our measurements, we decided to attach it to our bus floor and walls.

Butting it up against the 35mm X 70mm piece of wood we had used to tackle the curve of the bus wall, we manoeuvred it into place and used 40mm wood screws to attach it to the floor and the walls. This was just a very basic structure that still needed support however once screwed into place was already feeling solid.

Stepping back, we then took a good look for where we would start next. We found if you start with the most complicated bits first, it is easier to work out the errors if something was to go wrong. And we had so many issues! It sounds easy as I write it all down, but it’s not. We had problems with wood not aligning correctly, being the incorrect size, splitting, drill pieces breaking and more. It happens! This is why it took us so much longer than we initially planned.

The restrictions with installing an oven into a bus – 

So our next thing to tackle was where our oven would be placed. This was the main structural item that needed to be built into our kitchen framing and it was probably going to be the hardest.

We had purchased a Thetford dual fuel fan forced oven. There are a lot of restrictions with an oven inside a motor home. This is not something we had taken into account when we initially started the framing and our bus conversion plan and design. It needs to be certain distances from cupboards, walls, and anything else that could be a fire hazard. There needs to be a hole underneath where the gas can be tunneled so it can then go to an external vent outside. All these restrictions and regulations left us scratching our heads and coming up with new plans and workarounds.

Taking into account our bench top thickness, we start by measuring from the top down to where the bottom of our oven would be placed.

We then used our 19mm X 64mm wood to build a frame and place a piece of 7mm ply on top to provide a base support for our oven. After this, we built walls using 19mm thick wood to match our current framing. This stops any external droughts coming into the area where the oven will be located.

Cutting the bus kitchen bench – 

The next step was something we had greatly anticipated; the bench top.  It needed to be cut to size and then have the oven and sink holes measured and cut. We initially were going to have a wooden bench top; however decided due to the upkeep and maintenance of wood, we went with a laminate bench top instead. This also saved weight.

Measuring up the sink and oven was relatively simple; measure twice, cut once. So glad we did this! We just had to decide on their exact placement and take into account the overhang of the bench top at the front and rear. Once measured and drawn up we started with the sink hole. Pre-drilling a hole and then using a jigsaw allowed us to easily cut the hole required. The oven was even easier, still using the jigsaw slowly make the straight cuts.

Once it was put into place and checked to make sure it fit, we used 40mm wood screws to attach our base to our bench. It was screwed from underneath so the screws are hidden.

This process of the oven frame and bench top took an entire day. There were issues with the oven not fitting and constantly needing to make adjustments. We also had a measurement issue where we forgot to take into account the overhang for the bench top. It was super frustrating but we are so happy with how it turned out!

The next step in our bus kitchen frame will be to make our cupboards and install them. We are hoping as with everything that will be the easy part. We will also begin work on our lounge and anything else we can to finish our home!