Saurer V2
As announced in the previous column, here I want to summarize the essential points for the design of a housing structure, mine is not a Bible, but wants to be a tool for sharing so that you too can avoid the mistakes I made with the first construction.

The first construction is relatively simple and that's how I wanted it, that's fine, but it has its defects due to the first experience in the construction of a structure like this.
For example, I did not provide any space under the bed to put things away, or the heating in the shower, the coldest point of the house, at first I had not planned the installation of a roof window with ventilation, which I installed later and it is extraordinary, the access to the shower which is rather difficult and the lack of space for a proper toilet, a side entrance instead of a central one on the back, which for the interior arrangement is the worst thing, the relative lack of space traveling in two, both the interior itself and the possibility to arrange your things like at home, i.e. in a simple and accessible way.

All these details didn't bother me at first, because I knew them and they didn't bother me particularly, then slowly, using the little house more and more, having had some problems with the toilet, etc., now I realize that these things start to interfere with travel, because it is not optimal as I would like.

The planning of this little house, I think I can say that it has long exceeded 100h of work, but starting from the beginning, it will seem impossible, but I draw with Excel, because, for the simple fact that putting the cells all at the same size, that is in square mode and each square corresponds to a cm, I can very quickly realize the proportions and space in the various compartments.
To design theme I wanted to make a video, but unfortunately in this apartment the light is not the best.

Below I put some pictures of the project from Excel with some explanation.

First two words about the cell itself, let's start by saying that one night at Payerne I went to visit an acquaintance in Fribourg who also has a 6DM, he mounts as a cell, a cold room! at first very skeptical, I was surprised by its simplicity and robustness. Not thinking about it at the time, I soon realized that it's not so bad as a solution, isolated is isolated too, plus Laurent, if I'm not mistaken, added 3cm of polystyrene insulation, so he was able to hide several things behind the walls themselves.

My idea, stolen by him, is to have a cold room built this way:
To make the idea, the red line is where my current cell ends, this one, only 96cm longer, so under the meter! allows me to get a side access door first of all, as said before, to make the most of the space and finally, thanks to a better layout, to be able to put your things away properly.
The room will be on the base of a cold room, the corner behind at almost 45° will allow me to have the same rear angle of attack as now and exploiting the width of 250cm against the 230cm of the current, I gain some space still in the living area, which allows me to install benches of 1m.

This is the right wall seen from the inside, the first empty room on the left is the shower including toilet, which will not go from one side to the other but on this wall there should be two basic kitchen cabinets 60cm x 80cm and above a wall unit 60cm x 40cm, in blue we have the entrance door, the kitchen consists of 4 cabinets 60cm wide and finally raised above the garage, the bed.

This is the left wall seen from the inside, always on the left we find the bed above the garage, a sketch of the water tanks with the rather simple formula that tells me how many liters for each dm of length I can have with this height, why this height? because above the tanks I still have 40cm of space, which allow me to put some 60l Rako boxes that have a height of 32cm above the water tanks and if the door frame does not take up too much space, I can still pull out and put away the boxes on the left side too. Yes because the cans, even if it is a solution that I don't like very much, will be two of 50cm and will be on the left side, two to avoid that the water inside moves too much and one meter, because in this way I arrive at 440l of loadable drinking water (I will arrive also to this theme).
Then we find the two benches that have from back to back a distance of 205cm, which I also wanted this, so that the two benches can quickly become a bed, a bed of 205cm x 100cm!
On top of the benches there are also some wall cabinets, 2 of 40cm x 40cm and two of 60cm x 40cm, followed by 4 basic kitchen cabinets of 60cm x 80cm and two wall cabinets of 60cm x 40cm that will serve me as a wardrobe, and finally the shower including toilet that will have the size of 160cm x 80cm also like the current one, probably completely covered in stainless steel, solution in my opinion top!

The challenges of this project;
a lot, really a lot, it took me a lot of time and energy, but the result is a masterpiece to say the least, I really like it. At the beginning, I said to myself, start, a sketch and off on a piece of paper, and little by little it became all this. The biggest challenge I have to say was to fix a measure of length, which has then changed several times to get to the current result which is really good, because doubling the current space with 96cm more is not easy on a house (the current one) of 5m. 

The second biggest challenge, is to know your vehicle, I can not want to connect the batteries of the truck to those of the house and then put the batteries of the latter at the back of the vehicle, so the arrangement of each component has been thought out in detail. Then, define what I wanted inside, even if for me it was quite clear, a nice kitchen, a second bed that are then the benches that I could easily replace with 3-point belt blocks (that day I will become a dad later). Afterwards, a skylight passes man over the bed, a garage under the bed and a little more autonomy for the water, a shower with toilet where I could enter without having to do gymnastics and a "wardrobe" dedicated to the technique, in fact the furniture that will be placed near the shower, directly at the entrance on the right, will act as a technical room, but not only, as a good man, I also thought of you women, and what could be nicer than being able to wash at home? That said, done, I found at Fust a 4Kg washing machine that fits perfectly into a kitchen cabinet, in a few words it's as big as a dishwasher. But it consumes a lot of water, well, "it" consumes the same amount of water per wash that we use in two to take a shower, that is about 40l. Washing twice a week, and taking a shower every day, plus about 10l go around to cook, we arrive in 7 days to 430l of water consumption! so, we should be able to be autonomous for 7 days.
To date, with 280l I can keep 5 days without washing machine, so it becomes very interesting to be able to charge more water. The solar panels on the roof, well, I want to install two windows with fan, the skylight above the bed passes man, the hood for the kitchen, the space on the roof is not immense, and yet, yes it is, just put things in the right place, in fact I could install the beauty of 4 solar panels 360W for 1440W of installed power.
But, between the shower on the front and the waste water tank on the back, there are about 5.5m of road to do for the waste water, if the truck is on a slope? Then, here too the boat comes to our aid, in fact there are wells with attached pump that take care of the dirty work of sending the waste water to the appropriate tank. But, between the shower on the front and the waste water tank on the back, there is about 5.5m of road to go for the waste water, if the truck is on a slope?
Then, here too, the boat comes to our aid, in fact there are wells with attached pump that take care of the dirty work of sending the waste water to the appropriate tank. For the washing machine should not be a problem because it is equipped with its own water evacuation pump.
Another important challenge is the definition of how many windows it needs but above all the size, two large windows in the living room and kitchen area allow natural light to enter well and at the same time allow good ventilation, also because in anticipation of installing a hood above the cooker, the entry of air must be guaranteed.
The positioning of the Webasto, i.e. the heating was excluded under the bed, in fact being rather noisy, premise that in the current situation, the only thing that separates us from the noise of the heating is the mattress, which unfortunately is not pressed in its seat, but is rather free, this makes it easy to hear the noise, hence the decision to place it under one of the benches and more precisely the one furthest from the bed.
The choice of the path of the water pipes as well as the electrical pipes was really a feat, not wanting to have any more pipes, cables, wires on sight, I decided to add to the 7cm of insulation of the cell 5cm of polystyrene inside so that all the cables, wires, pipes, etc. can pass behind the walls and have a finished result, like at home.
Last, at home I have a PLC (programmable logic controller) that I do not use, and I thought to use it in this project to control the home automation of the cell, so all the accessories, lights, consumers, etc..
Because a PLC, a PLC gives me the freedom to choose which users to give power to and which not, based on the signals received, an example, I want an external switch that turns on my external lights and an internal one for the lights inside, then, I tell myself that this solution does not suit me, and I want to turn on the internal lights with the external one with the external switch, while only the internal ones with the internal one, well, it will be enough for me to change the management program and turn on the lights as I want.
I want a button that allows me to turn off everything, for example at the end of the trip or at the end of the season, well, I just need to program the PLC to turn off everything with this button. But I do not want to turn off everything, the refrigerator, through external or internal power supply, I want it to be always powered, even here I just need to change the program.