The Shulhan Aruch writes that it is forbidden to paint or plaster one’s home during the Nine Days, from Rosh Hodesh Ab until after Tisha B’Ab. It is, however, permissible to paint a synagogue during this period, as this constitutes a Misva. The rule of "Zeh Keli Ve’anvehu" requires enhancing and beautifying Misvot, and thus it is a Misva to enhance a synagogue’s beauty. This Misva overrides the restrictions of the Nine Days, and therefore a synagogue may be painted during this period. One’s home, however, should not be painted or redecorated during the Nine Days.
The Mishna Berura (Rav Yisrael Meir Kagan, 1839-1933) makes an exception in the case of a non-Jewish painter who is paid for the job, as opposed to an hourly rate. If the painter wishes to do the job during the Nine Days for reasons of personal convenience, he may be allowed to do so, even on Tisha B’Ab itself. The Mishna Berura writes that it is preferable in such a case to try to persuade the painter to delay the work until after Tisha B’Ab, even if this requires paying a bit extra, but if the painter insists on painting during the Nine Days, such as if he has another job afterward, one may allow him to paint during this period.
Another exception, which is mentioned by the Kaf Ha’haim (Rav Yaakob Haim Sofer, Baghdad-Israel, 1870-1939) in the name of other authorities, is that one my hire a Jew who needs work for his livelihood to paint during the Nine Days. Since this Jew needs the work to support himself, he may be hired for the job during the Nine Days.
Summary: One may not paint or redecorate one’s home during the Nine Days. If one hires a non-Jewish contractor who wants to do the job during the Nine Days, it is preferable to try to convince him to delay the work until after Tisha B’Ab, but if he insists on working during the Nine Days, and even on Tisha B’Ab, this is permissible. A Jewish worker who needs the job for his livelihood may be hired to work during this period. Synagogues may be painted during the Nine Days.
