There's masses of DIY information on dealing with all these problems in yachts. Power, water, sewerage, heating etc are all solved easily with off the shelf par

There's masses of DIY information on dealing with all these problems in yachts. Power, water, sewerage, heating etc are all solved easily with off the shelf parts available for this market. Practical boat owner is good magazine to find out about this kind of stuff in the UK. Insulation is a bit tricky because the water vapour generated by breathing and washing etc will condense on the inside of the metal shell of the vehicle, potentially causing problems with corrosion, mould growth and rot in any organic elements. Ideally you would seal up the bus, put in plenty of insulation and have mechanical ventilation with heat recovery. Choosing the correct insulation and making it vapour tight or ventilating the cold side is the hard part. Hygrothermal simulations are becoming quite easy to do these days so this may be the way to go with regards to designing the insulation.