Flexible piping includes a first, spiral-wound band forming an inner winding and a second, spiral-wound band forming an outer winding in covering relationship over the inner winding. Inner and outer spiral-wound bands of insulating material are wound between the inner and outer windings and over the outer winding respectively. An insulating sleeve receives the spiral-wound inner and outer windings and the inner and outer insulating material bands. A method and a machine for forming the flexible piping are also disclosed.