The Vaulted Room
Interpreters believe that whoever sees himself building a vaulted room (azaj) with fired bricks, especially if it's a cistern, it may indicate the discipline of his child. It is mentioned that gypsum and fired bricks are associated with the work of the people of hellfire and the pharaohs.
Per Ibn Sirin's Muntakhab al-Kalam fi Tafsir al-Ahlam