I'm still planning out the skoolie of my dreams, and have been making sketches based on the many floorplans I've seen here and elsewhere.
I've a 26 foot travel trailer I'm using for stroage, and will steal all of the appliances/tanks from it for the skoolie.
One thing that ALWAYS bugged me is the poor quality of the workmanship, cabinets and trims I've seen in "professional" rigs, even some of the $750,000 setups (I do finish carpentry, and timber framing, which is sorta like giant finish carpentry).
First, my floor covering will be installed full-width/length of the bus, it's easier to make the floor/cabinet interface look good this way, and simpler to install without a ton of special effort/cutting/fitting.
The floor insulation will be rigid foam (see below), with a T&G ply subfloor. I considered OSB T&G, but want to reduce chemical outgassing in this rather small enclosed space.
Walls will be insulated with Foil-faced foam sheets, joints foamed shut, unless I can find a guy that can spray foam in place in the rather thin wall structures without wasting materials/involving humungous labor trimming off excess.
I'm planning on building Euro-style frameless cabinets, with full-extension drawers everywhere space access is spotty. Bottom-mounted drawer slides will permit saving the inch of width that regular side-mounted slides waste, and all drawers (1/2 inch baltic birch ply) will be finger jointed with stiff bottoms, 1/4 or 1/2 birch ply as required by width for stiffness.
Cabinet joints will be rabbetted lockjoints for security/strength/stiffness.
The basic floor cabinet boxes will sit on separate 2x4 frames that allow a toe-kick area. This allows the space beneath the cabinets to be used for utility chases, and allows the (fairly) simple removal of cabinets to access the utilities if need be; the pipes/wires won't run through the cabinets themselves except where hooked into the appliance in that cabinet.
A 2x4 chase would allow plenty of pitch for drain/fresh water pipes over a fairly small run.
Wall cabinets will be similarly constructed of birch ply. I will scribe them in to the roof curve for esthetic reasons.
I will probably finish the cabinet interiors in a natural wood finish, but haven't decided whether to paint or stain the exteriors. If I can find nice book-matched sheets for the cabinet doors, I'll go that way (clear stained finishes).
I'm also mounting the water heater (tankless style) on it's own shelf, with sweated copper unions, so it can be pulled as a unit without major access problems.
In other words, I'm making stuff as modular as possible for service/replacement reasons. Plus, regular sized modules will allow rearrangement if need be, with less hassle.
And, modules will permit moving most/all of these same cabinets to another skoolie some day, if I wish.
For example, removing the sink cabinet for access/repairs would entail removing some screws, closing the water shutoffs, disconnecting the tailpiece/trap and supply hoses, and lifting it out as a unit.
I am debating not having a bath sink, to simplify plumbing/space considerations. I'd just use the kitchen sink for washing hands, brushing teeth, shaving (I'm such a guy). I'm certain women would object
Likewise the dinette will be ply construction, and somewhat modular.
I saw on the Busnut site a plan that puts closets across from the bathroom, so that when the closet doors are opened up, they enclose the bath in an 8x8 foot area. NICE! The rearmost closet door also provides some, uh, 'privacy' for the rear bedroom...especially nice if I have overnight guests over while attending some of the events I go to.
I'm considering good quality solid-core doors for their sound-absorbing qualities and dimensional stability.
I will be using a 2x4 'wetwall' for water/vent pipes between the kitchen sink area and the bath, cutting down on water pipe runs. All water manifolds and faucets will be sloped installations to permit easier draining of the water systems.
The shower stall will be a simple fibreglas shower floor pan, and home centers sell a fibreglas white or beige sheeting in 4x8 size for bath/shower walls. Shower curtains instead of a glass door will do the job, and save weight too.
I have seen articles in Fine Homebuilding magazine on foam insulation that is suitable (for loading reasons) under subfloors, adequate to support appliances and traffic WITHOUT floor sleepers. I will report it here if I find the specific brand/types info. Otherwise, search the Fine Homebuilding archives.
I am planning on insulating the holding tanks area, using floor grilles and the cold air return from the furnace through the holding tank area; the previously warmed air would keep the tanks from freezing, without dedicating a heat duct just to the tanks area.
I have plans for making the queen bed in the rear 'tip up' like a Murphy bed, so I can readily access a rear fold-down porch through the escape door, and likewise access storage cabinets/drawers.
I also like the idea of a passenger-side fold-down porch area, but weight and width concerns may make that difficult. In any event, that design feature would be down the road aways (literally).
So that's where I'm at right now. The search for a bus has begun, but will not be in earnest for a couple months.
I'm always open for suggestions/queries, so let please me know what you think.