Building living quarters in an enclosed trailer, such as one used for race car transportation, can provide accommodations designed specifically to the user's requirements. The project will almost certainly cost more than buying a ready-made alternative, but if you already own the trailer and parts are available, you can build a unique mobile home-away-from-home. First, think through and thoroughly plan the project.
Use graph paper and a pen to make a detailed drawing of the floor plan. Begin by drawing the shape and size of the enclosed trailer, showing where the doors and roof vents are located. Determine how much of the internal space can be used for living quarters, then draw a line to represent the internal wall separating the two parts. If a personnel door is to be installed in the partition wall, show it on the plan, including whether it will open into the garage area or into the living quarters.
Determine what level of comfort the living quarters must afford. Visit a recreational vehicle dealership or trade show to get ideas on what fixtures and fittings are available, how the cabinets and storage are set up to maximise space and where manufacturers locate their heavier equipment. Draw the desired appliances, sleeping quarters, living area, galley and bathroom on the floor plan.
Decide whether you want windows in the side walls, and if so mark them on the plan. If the enclosed trailer does not have an external personnel door and one will be needed, draw that in also. Every obstruction and feature must be noted before designing the plumbing and electrical services.
Choose between a basic 12-volt electrical system that provides light and a limited number of outlets, or full 120-volt circuits powered through a breaker board from a power connection. These considerations may effect the layout of the furnishings and cabinetry, so have them in mind when deciding how you intend to use the interior space.
Draw in enough plumbing to serve the galley and bathroom. This utility also can be self-contained, running from a storage tank and using a 12-volt pump, or be connected to a city water supply. Because enclosed trailers tend to be low-slung, a particular consideration is the storage and venting of waste water. Determine whether your trailer has enough axle space to accommodate waste tanks underneath.
Build the living quarters into the enclosed trailer in a logical sequence. Install windows, doors and roof vents first, then partition walls. Next insulate and panel the walls, floor and ceiling, and install large and heavy appliances such as the cooker, air conditioner and space heater. Fit the galley, bathroom, sleeping accommodation and cabinetry according to the plans, then use extra space for coat racks, shelving and closed storage bays.
Salvage yards are in business that specialise in parting recreational vehicles and trailers. Check to see if sourcing used parts will be viable.
Be aware of tongue weight. It is customary to build living quarters into the nose of enclosed trailers, and the addition of so much weight could affect towing characteristics.