Any enclosed area has a status of a
reshus hayachid,
even if the fencing is just a temporary structure. If, however, the fence is constructed in an inferior fashion (see below for a definition of inferior) and the enclosure is the size of a
bais sassayim
, it is forbidden to carry in the enclosure for a distance of more than four
amos
. It may be permissible to carry from the enclosure into another
karmelis
. According to some opinions, if three walls were constructed properly but the fourth one is inferior, it would be permissible to carry within the enclosure.
[
שו"ע שס, א, משנ"ב א, ד ו־ה, וביה"ל ד"ה כגון; ביאורים ומוספים דרשו, 8
]