In designing his house, Barnum was influenced by American architecture popular in New England states at the beginning of the 19th century.

These elements include a central temple front with flanking wings, articulation of the facade with pilasters linked by elliptical arches, and extensive use of delicately scaled details.

The neoclassical elements of the house's exterior are echoed in the ornate woodwork of several interior rooms, particularly the parlour.

He followed the lead of earlier loyalists in settling on the north side of Lake Ontario, along the main route which connecting York with Kingston.

James was responsible for dismantling the grist mill, indicating the family's decreased dependence on agriculture.

The Ontario Heritage Trust performed an extensive restoration of Barnum House between 1989 and 1991 in an effort to ensure the long-term conservation of the site.

In the ensuing years, the site was operated as a partnership between the Ontario Heritage Trust and the Barnum House Museum Foundation.