When the entire family wants to vacation and there's only the sedan to make the trip, where do we put all the luggage? Well, there's no one on the car roof so let's put it up there! A rooftop carrier is a great way to carry along additional suitcases, boxed up Christmas presents or that cumbersome purchase from the big-box store. Building a rooftop carrier will not only save money but also result in a platform fitted precisely to your car or van.
Wood or metal? Decide what to use to assemble the carrier. Metal is strong and durable but might be more demanding to work and shape in a home workshop. Wood is lightweight and easily cut and fastened together but can wither quickly over time in the weather. Sticking with wood, however, allows readily available hand tools to do the job. When the carrier is assembled, heavy coats of wood paint primer and a sturdy urethane wood deck paint will go a long way toward protecting the carrier from the elements.
The entire carrier will be fashioned from 2-inch by 2-inch square rails. Although pine lumber is inexpensive and abundant, consider using a harder wood such as oak for a quality project. Also needed are five rubber suction-cup feet large enough to fit on each wooden leg. These are available at most home supply stores in the hardware section. Finally, from an auto supply store, buy two adjustable nylon straps to secure the carrier to the car roof.
Using the wood rails, fashion a wide ladder design with each "step" 8 to 10 inches apart. Fasten each rail to three perpendicular rails to act as side frames and a centre support. Lay the rail step on top of the side pieces and connect with 3-inch deck screws. At each corner attach a 5-inch "leg" and also one in the middle of the middle support, for a total of five legs. Attach a large suction cup to each leg. A good adhesive to secure the suction "feet" is Dap Weldwood glue. A contact glue, it will secure rubber to wood easily and quickly.
Place the carrier on top of the car. Just like a toy bow and arrow, moisten the suction cups for a good seal. Use the nylon strapping to further secure the carrier by hooking to the recesses above each car door window.
If an enclosed car carrier is needed, use the ladder frame as the "floor" and add vertical joists 18- to 30-inches high depending on the size you need and then wall with either plywood or aluminium sheeting (available from a building supply dealer). Remember, however, to angle the leading wall of the carrier for better aerodynamics when the car is on the road. Attach the top with hinges on the front edge to provide access to the car carrier.