He was a contemporary of the Swiss painters Anton Graff, Jean Preudhomme, Angelica Kauffman, Jakob Emanuel Handmann, Johann Caspar Füssli.

As a young man Schalch made study trips to Germany and France.

In 1754 Schalch moved to London, where he soon met and received commissions to paint for members of the Royal Court.

Schalch was noted for his paintings of the Rheinfall in Schaffhausen, many of which were reproduced as engravings, making his name well-known.

The Museum zu Allerheiligen in Schaffhausen owns the largest collection of Schalch paintings and drawings.