Antonyms for the word "re-building" would be words that mean the opposite or the opposite action of rebuilding. These antonyms include words like destroying, tearing down, disassembling, deconstructing, breaking apart, and dismantling. These words refer to the act of taking something apart or demolishing it instead of repairing or restoring it. While rebuilding implies that something is being fixed or improved, antonyms like destroying and dismantling suggest that something is being destroyed or taken apart. These antonyms may be used in a variety of contexts, such as discussing home renovation, urban planning, or environmental conservation.