Completing a roof top fence during the 3 weeks: The fence is being built by a Jewish contractor and was begun weeks ago. It is 75% complete, but the roof is not yet safe. The roof top is used for plants and a large Succah and sitting. Can we have the fence finished during the three weeks?
Shalom, Thank you for your question. The law that forbids building and home improvements during these days of mourning for the Temple is much more limited than your question would seem to imply. Firstly it is only during the nine days from the first until the ninth of Av that we must refrain from building, not the whole three weeks from the 17th of Tammuz. Secondly, it is only building of "simcha" (joy) that is forbidden. Exactly what falls into this definition is not so clear - but a roof fence is certainly not in this category. Thirdly, any building to prevent anything dangerous is permitted (and maybe an obligation). As your roof is not yet safe, you may certainly finish the fence - and are obligated to do so, as the Torah commands us to fence off our roofs. (There are other leniencies also, but these are the main ones that apply to your question). May we merit to see the rebuilding of the Temple in our days - Blessings.