He is chiefly remembered for his designs of the Brigittines chapel and the tower of the Saint Nicholas Church, both in Brussels.

He had two brothers who were also artists: Jan Baptist van Heil was a portrait painter and Daniel van Heil was a landscape painter specialising in winter scenes or burning fires.

[3] When in 1648 Erasmus Quellinus was given the general artistic direction over the decorations for the Joyous Entry into Antwerp of the newly appointed governor of the Habsburg Netherlands Archduke Leopold Wilhelm, Leo van Heil worked as Quellinus' architectural assistant.

[6] In his time Leo van Heil was known as an architect, painter of flowers and insects and other small animals and perspectives (i.e. architectural works).

[5] His drawing of Tongerlo Abbey served as model for a print of Tongerlo Abbey in bird's eye perspective made by the engraver Wenceslaus Hollar.