There are five works, all in watercolor on paper, that depict interiors of chapels and churches in Antwerp.
The first is dated 1710 and shows an Interior view of the small Gothic St Anne chapel in de Keizerstraat in Antwerp.
A third work depicts the Interior of the chapel of the Jesuit college in the Hof van Liere (Rhode Island School of Design Museum) in the Prinsstraat in Antwerp.
Casteels also depicted the interior of the Cathedral of Our Lady, but the location of this work is unknown.
They are not of a very high painterly quality but serve as interesting documentation about these buildings that are still in existence in Antwerp.