If a person is having construction work done in his house, may he allow the work to continue on Tisha B’Ab, or must he instruct the workmen not to work on that day?
When it comes to construction work in one’s home on Shabbat, Halacha distinguishes between a builder hired on an hourly rate, and a contractor hired "Be’kablanut" – meaning, that he is paid for the job, and not by hour. One may not allow a non-Jewish builder to work in one’s home on Shabbat if he is paid by the hour, since he will be receiving payment for the work performed on Shabbat. In the case of a non-Jewish contractor, however, it would be permissible, in theory, to have him work in one’s home on Shabbat, since the contractor determines his work schedule and is not getting paid specifically for working on Shabbat. In practice, it is forbidden to allow even a contractor to work in one’s home on Shabbat, because it may arouse suspicion among neighbors who might assume that the workers are paid per hour. The Sages enacted a provision forbidding all construction work in one’s home on Shabbat, in order to avoid suspicion.
On Tisha B’Ab, however, so such provision applies. Since the entire institution of Tisha B’Ab applies only on the level of Mi’de’rabbanan (Rabbinic enactment, as opposed to Torah law), it may be treated more leniently in this regard. It is therefore permissible to allow construction work to proceed in one’s home on the day of Tisha B’Ab, assuming the workers are not Jewish and the contractor is paid for the job, and not by the hour. This is the ruling of Hacham Ovadia Yosef, as well as of Rav Pinhas Zevihi, in his work Migdal David (listen to audio recording for precise citation).
Among the prohibitions we observe during "Shabua She’hal Bo" – the week in which Tisha B’Ab falls – is a prohibition against washing clothes and wearing freshly-laundered clothes.
A question arises concerning women who observe the "Shiba Nekiyim" – the seven "clean days" before immersing in the Mikveh – during the week of Tisha B’Ab. Halacha requires a woman to wear whites during these seven days, so that in the case of a stain it can be determined whether or not it was caused by bleeding. If a woman has only freshly-laundered whites during the week of Tisha B’Ab, is she allowed to wear them to fulfill the Halachic requirements of the "Shiba Nekiyim"?
Halacha allows a woman to wear the freshly-laundered whites in this case, because the prohibition against wearing fresh clothing during the week of Tisha B’Ab does not apply in situations of a Misva. The Rabbis did not intend to override Misvot when they enacted this prohibition, and therefore wearing freshly-laundered clothing is permissible for the purpose of a Misva, such as the observance of "Shiba Nekiyim." In fact, Hacham Ovadia Yosef rules that when necessary, a woman may ask her gentile housekeeper to wash whites for her during the week of Tisha B’Ab. (According to the Rama, a woman may even wash whites herself during this week if she needs them for the purpose of the "Shiba Nekiyim.")
Another application of this rule is a situation where a person had his Tallit dry cleaned, and it was returned to him during the week of Tisha B’Ab. Here, too, it would be permissible to wear the freshly-cleaned Tallit, since this is done for the purpose of a Misva.
Summary: One who is having construction work done by a non-Jewish contractor in his home may allow the work to continue on Tisha B’Ab, assuming that the contractor is paid for the job, and not by the hour. Halacha forbids wearing freshly-laundered clothing during the week of Tisha B’Ab, except when this is necessary for a Misva. Thus, if a woman observes the seven "clean days" before immersion and her only whites are freshly-laundered, she may wear them during the week of Tisha B’Ab, and one may wear a freshly-cleaned Tallit during the week of Tisha B’Ab.
