How to Convert a Box Truck into a Motorhome

Start with a sketch of the interior space available in the truck body. It can be a simple rectangle indicating the length and width of the inside of the body. Note the position of the side door if there is one. Use this drawing to design the layout of your camper and plan where the bathroom, bedroom and eating area will be.

Draw chalk lines on the floor of the body to match the location of the walls in your plan. Also draw the outline of the major features of your camper, such as the bed, closets, bathroom fixtures and dining area. Draw the lines to match the dimensions of the actual furniture and fixtures you will install in your camper.This will avoid surprises when the actual construction is underway.

Construct walls with two by four inch lumber framing. Use three inch deck screws and polyurethane glue to build the walls and attach them to the truck floor and exterior walls. Install electrical boxes and wiring for the lights and receptacles before sheathing the walls with wood paneling. Use 14 gauge stranded automotive wiring for this work as this type of wire stands up better to the vibration of a motorhome than does house-type wire.

Install a prehung hollow core door for the bathroom. Secure the door to the wall studs with three inch deck screws. These doors are low priced at home supply stores and are very light and strong. Use hollow core door for any other rooms your box truck camper may have. Prehung doors are the easiest to install because the come assembled with exterior trim and installed hinges.

Add at least one RV-type roof vent to the roof of the truck body. Cut through the roof with a reciprocating saw according to the template supplied with your roof vent. You may need a helper on the roof to install the vent. He can put the upper half of the vent through the hole and hold it in place while you attach the screws on the inside which hold the vent together and clamp it in place.

Install any windows in the body in the same manner as the roof vent. Check RV salvage yards for windows to save a lot of money.

Install the fresh water tank in a closet, in a storage box under a dinette seat or under the sink. Mount the 12 volt water pump close to the tank and connect the two with plastic tubing. Use plastic tubing to route the water to the tap in the sink and to the bathroom if a flush toilet will be installed.

Fabricate a bracket under the truck body to mount the tank for the waste water from the sink. Connect the tubing for the drain to the sink.

Mount the converter in a closet or under a dinette seat. Connect the wiring from the output side of the converter to your deep cycle battery. Connect the 14 gauge stranded wiring from your 12 volt lights and waterpump to the battery. Wire the input side of the converter to one of the fuses in the 30 amp box, which should be located in a dry and accessible area of the camper. Connect any electrical receptacles you installed to the other fuse in the box. Connect the 30 amp camper electrical cord to the input connections in the fuse box. When parked at a campsite plug the cord into the 30 amp receptacle to provide electrical power to your camper. A 30 amp box is used because many campgrounds only supply 30 amps to the campsites.

Put a portable toilet in the bathroom, fill the water storage tank and your truck is ready to be a motorhome. To make it more like a commercial motorhome, cabinets, a flush toilet, septic holding tank, hot water heater, propane system and a refrigerator can be added at a later date as your time and budget allow.