The Beam
Interpreters have mentioned that seeing a beam split lengthwise into two halves without falling may indicate a doubling of everything associated with the house. Additionally, wood and beams in construction are interpreted as symbolizing a hypocritical man who bears people's burdens, and their breakage could signify the death of such a man.
Per Ibn Sirin's Muntakhab al-Kalam fi Tafsir al-Ahlam
Note: These are traditional scholarly interpretations (ijtihad) drawn from a specific classical source — not a binding religious ruling, fortune-telling, or a prediction of the future.