The word "re-side" refers to the act of fixing or repairing a building's walls or adding new siding to make it look new. Antonyms for this term include "demolish," which means to destroy completely, and "neglect," which means to ignore or abandon something until it falls into disrepair. Alternately, an antonym for "re-side" could be "leave as is," indicating a choice not to make any changes to the exterior of a building. Another possible antonym is "downgrade," indicating a reduction in quality, value, or appearance. Ultimately, the choice of antonym will depend on the context in which the term is being used.