Question: check up better
Undergarments, socks, and towels get soiled readily/constantly because of the hot weather and sweat. These items are worn not for pleasure, but to absorb sweat and soil constantly. Can they be washed during the 9 days?
Before answering your question, the poskim only allow changing underwear, socks etc. if not changing will cause the person irritation and discomfort, but not that it is permitted to change as much as we like. It is hard to picture a private home getting their towels so dirty so quickly. In the event that all of one’s garment got used up and he doesn’t have anything that can be worn, it is permitted to wash what is needed.
See R’ Eider on the three weeks and Rivivos Efrayim 3-340 in the name of R’ Moshe Feinstein zt”l.