guard chambers

See how you translated this in Ezekiel 40:7.

sixty cubits

See how you translated these "long" cubits in Ezekiel 40:05.

This was a covering in front of an entrance with columns or posts for support. See how you translated this in Ezekiel 8:16.

about 27 meters

Possible meanings are 1) "closed windows" or 2) "windows with shutters" or 3) "narrow windows."

"the porches also had closed windows all around"

jambs are the sides of a wooden frame of a door