Abstract: A method for computer aided design of conduit comprising: creating a library of specification information and a library of drawing characteristics related to a plurality of element types and bundles. An element type is selected, and an identification key is calculated for the selected element type, forming a graphics object. The selecting of element types and the calculating of identification keys is repeated, forming an updated graphics object. Specification information and drawing characteristics are retrieved from the libraries and stored in association with each selected element type. At least two element types are selected to form a bundle. An identification bundle key is calculated for the bundle. Selection of element types to form additional bundles is repeated, calculating identification bundle keys or each additional bundle, forming an updated bundle graphics object. Specification information and drawing characteristics for the bundles are retrieved and stored in association with the bundles.