Must one re-pray the Friday Prayer that he performed in his room, following the Imam of the mosque, given that there were barriers between him and the mosque, and he doubts the validity of his prayer?

According to some scholars, Friday prayers performed in a building outside the mosque are valid when there is a need, provided that the Takbir is heard or the Imam is seen. Some, however, do not validate following the Imam if the building is enclosed. Since the questioner did not mention that his prayers were due to a need, he must repeat and make up those prayers as Dhuhr prayers. If he does not know their exact number, he should strive to make up what he believes to be the correct number to clear his conscience.