To build an outdoor kayak rack, start with 3-inch PVC pieces to create a base. Measure your kayaks to ensure the base is wide enough to accommodate them easily without scraping them. Construct a wide rectangle from the PVC using pipe, elbow connectors and two T connectors on each end of the rectangle to the dimensions that fit your kayaks.
Next, build the side towers that hold the kayaks. Adjust the height of the towers depending on how many kayaks you own or want to own. An average kayak rack easily holds six kayaks. Add 2 feet in height for every two kayaks. For every 2 feet, a four-way connector goes onto the pipe to make room for the kayak arms.
Construct the kayak arms about 3 feet long. The arms connect to each side of the tower. Cut as many arms as there are kayaks. Place the arms into the four-way connectors, and the body of the rack is complete.
Decide if you want to paint the rack or leave it white. To paint it, lightly sand the PVC down with a sander to allow the paint to dry in place, and use a UV-resistant paint to withstand the sun exposure.