An apparatus and method for mounting a buoyancy module onto a rigid pipe having a clamp. In one embodiment the clamp includes pads for clamping onto the outer surface or coating of the rigid pip, the pads having a teeth or serrations formed thereon for gripping the outer surface of the pipe. In a second embodiment, the clamp includes one or more coil springs formed from a resilient material adapted to be wound around the outer circumference of the pipe. The method for mounting a buoyancy module onto a rigid pipe includes the steps of reducing the outer diameter of the pipe at a location of the pipe to which a buoyancy module is to be attached and subsequently mounting a buoyancy module at such location.