His father was Philip Poelaert (1790–1875), a former architecture student at the Royal Academy of Fine Arts in Brussels.

The young Poelaert also trained there under Tilman-François Suys, and then in Paris under Louis Visconti and Jean-Nicolas Huyot.

Poelaert himself resided in the Marolles, only a few hundred metres from the building, on the Rue des Minimes/Minimenstraat, in a house adjoining his vast offices and workshops and communicating with them.

Nonetheless, many angry citizens personally blamed Poelaert for the forced relocations, and the expression skieven architek (meaning "crooked architect") became one of the most serious insults in the dialect of the Marolles.

[5] Poelaert retired in 1874 to his villa at the Grande Grille, on 363, avenue de la Reine/Koninginnelaan, in the then-rural village of Laeken.