Is it illegal for someone to use the property to wash clothes?

Illegal. According to relevant public information, neither the owner nor the property management company can occupy the parts of the property and public facilities without authorization. If it is really necessary to occupy * * * parts and public facilities, the relevant formalities shall be handled in accordance with the provisions after obtaining the consent of the relevant owners, owners' congress and property service enterprises. Article 54 of the "Regulations on Property Management" stipulates that those who use the parts of the property or facilities and equipment to conduct business shall go through the relevant procedures in accordance with the provisions after obtaining the consent of the relevant owners, owners' congress and property service enterprises. Owners' income should be mainly used to supplement special maintenance funds, and can also be used according to the decision of the owners' congress.