Rashi: In front of these chambers was a wide path ? a space of 50 Amos, like the appearance of the path of the chambers in the north, written above. Radak (10) ? it says k'Mar'eh, for this was a prophetic vision; he did not see the matter itself.

Vilna Gaon: Also in front of these chambers was a path of 10 Amos from east to west.

Malbim: Also between Lishkos ha'Chamishim and the Geder was a path of 10 Amos, just like for the north chambers (between Lishkos ha'Esrim and Lishkos ha'Me'ah). This is because Lishkos ha'Chamishim were like Lishkos ha'Me'ah in every way, including the size of the path by them, except that the former were square, and the latter were twice as long as their width.

Rashi: The length of the northern chambers was like the length of these, and similarly for their width.

Vilna Gaon, Malbim: These chambers were square - 50 by 50.

Rashi: All the exits, properties and entrances [of these chambers] were like those of the north.

Malbim: Their forms were the same, and their Halachos (they were not Kadosh), and their primary openings were to the north.