Thanks to the great climate in California I'm lucky to be able to cycle to work every day without too much thought about the weather. The van will be primarily used for weekend trips but also as an "occasional driver". Since I'm not living in the van long term the RWB & low roof were compromises to make it more practical day-to-day.
I'm into rock climbing, photography (particularly at night), walking and generally hanging out in nice places. This just means that a large living space isn't top priority as I plan to be in the van only to drive places, briefly in an evening after the activities, but mostly to sleep. Therefore it'll be a relatively simple conversion with a focus on the basics: road noise, heat insulation, airflow, light, practical storage & sleep comfort.
Perhaps the biggest reason for it being simple is that I have no idea what I'm doing and yet I'm already committed to doing the bulk of the work myself.
I've already covered most large surfaces with Dynamat Xtreme. A single "mega pack" contains 9 sheets of 24"x48" which so far looks to have me covered - although at $289.99 it's really not cheap! While there are a bunch of other alternatives (e.g. Roadkill) that run about half the price, Dynamat Xtreme appears to be hands down the most heavily recommended product.
These noise isolation products generally require 25-50% panel coverage to significantly cut down on panel vibration. I'll write a more detailed entry later on but it's fair to say that initial impressions are good.
Insulation is a double-edged sword. A well insulated van will retain heat through a cold night and keep out the heat during a hot day -- up to a point. In the day the reverse is true - a van left baking in the sun all day long will get hot no matter how well insulated but that insulation will prevent the hot air from getting out.
I've come across arguments for not insulating vans at all in hot climates like California, however from personal experience I know that it can still get very cold at high altitudes, with significant wind or in open areas (deserts) at night. Before reading more, please go ahead and follow the previous link as it is without doubt the most comprehensive round-up of different types of van insulation, as well as great explanations of radiation, conduction, convection & radiant barriars that I've found.
Armed with some excellent information on the subject I've ordered a 150 sq ft roll of 3M Thinsulate which I hope will handle the whole of my van. Thinsulate generally appears to be shipped by a frequent van conversion forum member called Hein.
Again, more detail to come once I've insulated the van, but generally speaking Thinsulate makes sense because it's easy to work with, doesn't require worrying about vapour barriers and has a good but not crazy R-value (e.g. it'll keep me warm in California on cold nights, but perhaps not in more frigid areas).
Airflow (and light)
Airflow & insulation are not really seperate topics as they have a big impact on each other. Airflow is key to both keeping a van cool and free of moisture. In the insulation scenario above where a heavily insulated van heats up during the day, massive airflow is one way to quickly exchange the hot air inside with cooler air from outside.
A powered fan vent is one way to exchange this air - get back to a hot van in the evening, open the vent and crank the fan. The vent might be left open during the night, optionally with the fan running (on a thermostat) to increase airflow and remove moisture.
In our exhaust vent example the air needs to come from somewhere. This might be a cracked window or door or perhaps a dedicated floor vent. Such an idea is something I'm definitely considering as being placed at the front floor of the van (cool air) it would pass through the back and pass out of a roof vent (hot air) promoting airflow. Because it's always open this would work during a hot day when it's not feasible to leave open a window or door due to risk of theft.
Currently my plan is uncertain - I am having a Ford factory glass window with opening sub-window retrofitted behind the driver side soon. This will allow more light and air but beyond that I'm still undecided:
A standard 14x14" roof vent (powered or otherwise) would not only raise the height of the roof by 2-3" (no more parking in my garage) but would also be an obvious marker of a converted van.
A custom sunroof (such as CR Laurence's ridiculous 22"x38" NewPort) has the benefit that it would be largely flush with the roof (and therefore relatively stealthy) but would be unpowered and could not be left open during the day. There's also a pretty hefty cost both in buying the sunroof & having it fitted. Such an option is tempting though as you'd get crazy amounts of light during the day and an opportunity to see the stars or rain while sleeping at night.
Practical storage & sleep comfort
Standard van layouts often come with rock 'n' roll beds (seats that fold flat at night) that occupy about 4/5 of the internal width as well as cupboards along the side away from the door, often including a small kitchen the fridge, hobs & sink. Clearly these are optimised for day use and while there may appear to be a lot of storage spaces, the ability to stash larger items is limited.
I'll be installing a permanent bed at roughly 4/5 width at the back of the van, leaving an empty space at the side to allow storage of larger and longer items. This might potentially include space for a bike, bouldering mat, etc.
The bed will be raised quite high from the ground to leave space underneath for storing more large items, likely to be held in large, pull out bins. In future I may look at installing a single heavy duty drawer similar to that in Alex Honnold's van, although this would mean stripping the interior for general cargo use becomes much more difficult. Clearly there will be a balancing act between under bed storage and sleeping height -- I'm not going to be able to sit up straight in the bed but it would be nice to be able to sit up leaning against a side wall. I'm currently aiming for a US full size mattress which is approximately equivalent to a UK double. This will leave approximately one metre of space towards the front. The mattress will be foam, perhaps even from one of the well-known online retailers such as Leesa or Casper (depends on mattress depth).
At both sides of the bed I'll install small cargo nets for storing smaller items such as 'phones, wallet, keys, etc. Extending and collapsing tripods can be particularly annoying when shooting subjects immediately outside of the vehicle, so I'll experiment with a simple double loop system so that I can stash them on the ceiling at full extension.
Towards the front of the van I plan to have a small set of drawers for storing cook and tableware along with a top surface suitable for preparing and perhaps cooking food. I am not installing running water, a stove or a powered fridge. Most likely all cooking will be done on a small table attached to the larger of the 60/40 doors that will fold down outside of the van with the door open. Any perishable foods will be stored in a cooler box (sufficient for weekend trips).
I will install rotating bases to one or both of the cab chairs to increase usable space in the back. A freestanding collapsible table will likely be stored somewhere in the van for use from the cab chairs (think laptops). The table will be freestanding so that it can also be used outside of the van when weather permits.
Finish and panelling
Both the walls and ceiling will be panelled with a thin ply. For the roof I may look at using a low plush automotive-style carpet to help reduce sound reflections inside (this may not be necessary with a large foam mattress). On the free wall at the back (i.e. without an adjoining bed) I may use a thicker ply suitable for installing fixtures to help make the side space more usable. Wall finish is TBD but they may just be varnished and left as-is.
Finally the floor will be either lino or a low plush outdoor carpet. At the moment the practicality of lino is winning as do not plan to allow the floor to be removed easily.
Initially the van will not have a leisure battery. That said, I will run wiring throughout to allow a relatively straightforward install in the future.
The ability to run laptops and use a roof vent fan is quite a compelling reason.
Already present in the rear are stock lights. I may or may not expose these but will likely not install my own lights as cheap, battery powered lights that can be centrally controlled from a remote control are plentiful on Amazon.