I cut the rib shapes out of styrene material and added a trim of vinyl hosing from the hardware store, this helped beef up the design and also covers imperfections in my cutting that I don't have to sand out.  The bulk of the work is done with plastic sheets and strips in very shapes and sizes manufactured by Evergreen Scale Models.  If you don't have an awesome local hobby shop like I do you can order it from online.  I added various other sprinkler parts and different shapes of wire to make it look more fancy as well as leftover parts from other models.  I wrapped the vinyl tubing around all the exposed edges and the door and constructed hinges from scratch using a toothpick as the hinge pin.