I rent a house from a gentile and my children play on the roof. There is a two foot high wall around the roof. I understand that two feet does not satisfy the Torah requirement to construct a ma’ake. Am I required to build on top of the wall in order to reach the height that is required by the Torah?
You are correct that two feet does not fulfill the Torah requirement to construct a ma’ake since the height that the Torah requires is ten tefachim which is about three feet. The issue which requires clarification is whether a house which is rented by a Jew from a gentile requires a ma’ake.
When the Torah introduces the law of ma’ake, the Torah writes, “When you build a new house you must construct a fence around the roof.” This would seem to indicate that the requirement to build a ma’ake falls on the one who owns the house. However, when the Gemara discusses which obligations are the responsibility of the property owner and which are the responsibility of the renter, the Gemara rules that it is the renter who is responsible to build the ma’ake and not the property owner. This would seem to indicate that a renter is also required to erect a ma’ake.
One approach is that of the Sefer Hayeraim (Mitzvo 234). He deduces from the Sifrei that says that the responsibility to build a ma’ake falls not only on one who builds a house but even on one who purchases or inherits a house, that one who rents a house is not obligated by Torah law to build a ma’ake since the Sifrei does not include one who rents a house. It only broadens the requirement to include owners who did not build the house.
He then addresses the obvious question that how can the Gemara then rule that the renter is responsible to build a ma’ake and not the owner if the Torah requires the owner and not the renter to build a ma’ake? He answers that the Rabbonon changed the Torah law, a power that they have since one is violating a Torah command only by inaction. The rationale of the Rabbonon is that one who occupies a property is interested in a wall around the roof whereas an owner who does not occupy the property is not interested. Therefore, in order to ensure fulfillment of the Torah’s law that there must be a wall around a roof, they placed the responsibility on the tenant and not the owner.
The Maharil Diskin (Responsa Kuntress Acharon 256) deduces that according to this approach one who rents from a gentile is not required to erect a ma’ake, since a renter does not have his own obligation. The only reason the Rabbonon required one who rents from a Jew to erect a ma’ake is in order to ensure that the Jewish owner’s obligation to erect a ma’ake is fulfilled. Since the Torah does not require a gentile homeowner to erect a ma’ake, the Jewish renter is not required to erect it on his behalf. The Devar Avrohom (1, 37, section 22), for slightly different reasons, concludes as well that one who rents from a gentile is not required to build a ma’ake.
While there are many Rishonim who follow the approach of the Sefer Yeraim, there are others who disagree. For example, the Rosh and Nemukai Yosef have a different approach. They explain that the Gemara rules that a renter is required to erect the ma’ake since this falls into the general criteria which determine which repairs are the responsibility of the owner and which are the responsibility of the tenant. This approach holds that both the owner and the renter are equally required by the Torah to erect the ma’ake and the Chazal just established criteria to determine which of the two must actually erect the ma’ake. According to this approach, one who rents from a gentile is required to erect a ma’ake because renters are required to erect a ma’ake.
The above discussion was just whether a renter has the positive mitzvah to erect a ma’ake. However, besides the positive requirement to erect a ma’ake, there is a negative injunction prohibiting one from maintaining in his possession anything which can possibly cause death since the Torah writes, “One’s house must not cause death.” Thus, for example, the Gemara (Bava Kamo 15B) writes that one is not allowed to own a dangerous dog or possess a non-sturdy ladder because one could die from them. Since one who falls from a roof which is even just ten tefachim above ground can die (ruling of the Gemara Bava Kama 51A) one who lives in a house which lacks a ma’ake is required to erect a ma’ake in order to avoid violating this negative injunction. (Probably you would anyway want to raise the height for the safety of your children.)
Thus we have established that there is a dispute whether you have a positive command to erect a ma’ake but you certainly must erect one in order to avoid violating a negative command. The key difference is that if there is a positive command to erect a ma’ake then one makes a brocho, whereas if there is only a negative command there is no brocho since there are no brochos for avoiding negative prohibitions. (For example there is no brocho when one refrains from speaking loshon hora even if he made a great effort to do so.)
In conclusion, you must raise the height of the present ma’ake. However, when you do so you may not recite a brocho.
We should note that when one is required to build a ma’ake like, for example, if one builds his own house, he can only recite a brocho if he builds part of the ma’ake. If a different Jew constructs the m’ake he is the one who recites the brocho, and if it is constructed entirely by a non-Jew no one can recite the brocho.
Since one should try to fulfill mitzvas himself, the proper way is that one should start the building the ma’ake, and if necessary have someone else conclude the construction.